diff --git a/pyproject.toml b/pyproject.toml
index 868a78724bb8..b5b94dec1310 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -48,6 +48,7 @@ module = [
     "sqlalchemy.*", # https://docs.sqlalchemy.org/en/14/orm/extensions/mypy.html
     "transaction.*",
     "venusian.*",
+    "webob.*", # https://github.com/python/typeshed/pull/9874
     "whitenoise.*",
     "wtforms.*", # https://github.com/wtforms/wtforms/issues/618
     "yara.*",
diff --git a/tests/unit/accounts/test_forms.py b/tests/unit/accounts/test_forms.py
index 850dd3f678b4..6d5d67dbc244 100644
--- a/tests/unit/accounts/test_forms.py
+++ b/tests/unit/accounts/test_forms.py
@@ -17,6 +17,8 @@
 import pytest
 import wtforms
 
+from webob.multidict import MultiDict
+
 from warehouse import recaptcha
 from warehouse.accounts import forms
 from warehouse.accounts.interfaces import (
@@ -36,7 +38,9 @@ def test_creation(self):
         user_service = pretend.stub()
         breach_service = pretend.stub()
         form = forms.LoginForm(
-            request=request, user_service=user_service, breach_service=breach_service
+            request=request,
+            user_service=user_service,
+            breach_service=breach_service,
         )
 
         assert form.request is request
@@ -84,7 +88,7 @@ def test_validate_password_no_user(self):
         )
         breach_service = pretend.stub()
         form = forms.LoginForm(
-            data={"username": "my_username"},
+            formdata=MultiDict({"username": "my_username"}),
             request=request,
             user_service=user_service,
             breach_service=breach_service,
@@ -110,7 +114,7 @@ def test_validate_password_disabled_for_compromised_pw(self, db_session):
         )
         breach_service = pretend.stub(failure_message="Bad Password!")
         form = forms.LoginForm(
-            data={"username": "my_username"},
+            formdata=MultiDict({"username": "my_username"}),
             request=request,
             user_service=user_service,
             breach_service=breach_service,
@@ -141,7 +145,7 @@ def test_validate_password_ok(self):
             check_password=pretend.call_recorder(lambda pw, tags: False)
         )
         form = forms.LoginForm(
-            data={"username": "my_username"},
+            formdata=MultiDict({"username": "my_username"}),
             request=request,
             user_service=user_service,
             breach_service=breach_service,
@@ -183,7 +187,7 @@ def test_validate_password_notok(self, db_session):
         )
         breach_service = pretend.stub()
         form = forms.LoginForm(
-            data={"username": "my_username"},
+            formdata=MultiDict({"username": "my_username"}),
             request=request,
             user_service=user_service,
             breach_service=breach_service,
@@ -226,7 +230,7 @@ def test_validate_password_too_many_failed(self):
         )
         breach_service = pretend.stub()
         form = forms.LoginForm(
-            data={"username": "my_username"},
+            formdata=MultiDict({"username": "my_username"}),
             request=request,
             user_service=user_service,
             breach_service=breach_service,
@@ -268,7 +272,7 @@ def test_password_breached(self, monkeypatch):
         )
 
         form = forms.LoginForm(
-            data={"password": "password"},
+            MultiDict({"password": "password"}),
             request=request,
             user_service=user_service,
             breach_service=breach_service,
@@ -302,7 +306,7 @@ def test_validate_password_ok_ip_banned(self):
             check_password=pretend.call_recorder(lambda pw, tags: False)
         )
         form = forms.LoginForm(
-            data={"username": "my_username"},
+            formdata=MultiDict({"username": "my_username"}),
             request=request,
             user_service=user_service,
             breach_service=breach_service,
@@ -335,7 +339,7 @@ def test_validate_password_notok_ip_banned(self, db_session):
         )
         breach_service = pretend.stub()
         form = forms.LoginForm(
-            data={"username": "my_username"},
+            formdata=MultiDict({"username": "my_username"}),
             request=request,
             user_service=user_service,
             breach_service=breach_service,
@@ -357,7 +361,7 @@ def test_create(self):
         breach_service = pretend.stub()
 
         form = forms.RegistrationForm(
-            data={},
+            formdata=MultiDict(),
             user_service=user_service,
             recaptcha_service=recaptcha_service,
             breach_service=breach_service,
@@ -368,7 +372,7 @@ def test_create(self):
 
     def test_password_confirm_required_error(self):
         form = forms.RegistrationForm(
-            data={"password_confirm": ""},
+            formdata=MultiDict({"password_confirm": ""}),
             user_service=pretend.stub(
                 find_userid_by_email=pretend.call_recorder(lambda _: pretend.stub())
             ),
@@ -384,7 +388,9 @@ def test_passwords_mismatch_error(self, pyramid_config):
             find_userid_by_email=pretend.call_recorder(lambda _: pretend.stub())
         )
         form = forms.RegistrationForm(
-            data={"new_password": "password", "password_confirm": "mismatch"},
+            formdata=MultiDict(
+                {"new_password": "password", "password_confirm": "mismatch"}
+            ),
             user_service=user_service,
             recaptcha_service=pretend.stub(enabled=True),
             breach_service=pretend.stub(check_password=lambda pw, tags=None: False),
@@ -401,10 +407,12 @@ def test_passwords_match_success(self):
             find_userid_by_email=pretend.call_recorder(lambda _: pretend.stub())
         )
         form = forms.RegistrationForm(
-            data={
-                "new_password": "MyStr0ng!shPassword",
-                "password_confirm": "MyStr0ng!shPassword",
-            },
+            formdata=MultiDict(
+                {
+                    "new_password": "MyStr0ng!shPassword",
+                    "password_confirm": "MyStr0ng!shPassword",
+                }
+            ),
             user_service=user_service,
             recaptcha_service=pretend.stub(enabled=True),
             breach_service=pretend.stub(check_password=lambda pw, tags=None: False),
@@ -416,7 +424,7 @@ def test_passwords_match_success(self):
 
     def test_email_required_error(self):
         form = forms.RegistrationForm(
-            data={"email": ""},
+            formdata=MultiDict({"email": ""}),
             user_service=pretend.stub(
                 find_userid_by_email=pretend.call_recorder(lambda _: pretend.stub())
             ),
@@ -430,7 +438,7 @@ def test_email_required_error(self):
     @pytest.mark.parametrize("email", ["bad", "foo]bar@example.com", "</body></html>"])
     def test_invalid_email_error(self, pyramid_config, email):
         form = forms.RegistrationForm(
-            data={"email": email},
+            formdata=MultiDict({"email": email}),
             user_service=pretend.stub(
                 find_userid_by_email=pretend.call_recorder(lambda _: None)
             ),
@@ -445,7 +453,7 @@ def test_invalid_email_error(self, pyramid_config, email):
 
     def test_exotic_email_success(self):
         form = forms.RegistrationForm(
-            data={"email": "foo@n--tree.net"},
+            formdata=MultiDict({"email": "foo@n--tree.net"}),
             user_service=pretend.stub(
                 find_userid_by_email=pretend.call_recorder(lambda _: None)
             ),
@@ -458,7 +466,7 @@ def test_exotic_email_success(self):
 
     def test_email_exists_error(self, pyramid_config):
         form = forms.RegistrationForm(
-            data={"email": "foo@bar.com"},
+            formdata=MultiDict({"email": "foo@bar.com"}),
             user_service=pretend.stub(
                 find_userid_by_email=pretend.call_recorder(lambda _: pretend.stub())
             ),
@@ -475,7 +483,7 @@ def test_email_exists_error(self, pyramid_config):
 
     def test_prohibited_email_error(self, pyramid_config):
         form = forms.RegistrationForm(
-            data={"email": "foo@bearsarefuzzy.com"},
+            formdata=MultiDict({"email": "foo@bearsarefuzzy.com"}),
             user_service=pretend.stub(
                 find_userid_by_email=pretend.call_recorder(lambda _: None)
             ),
@@ -492,7 +500,7 @@ def test_prohibited_email_error(self, pyramid_config):
 
     def test_recaptcha_disabled(self):
         form = forms.RegistrationForm(
-            data={"g_recpatcha_response": ""},
+            formdata=MultiDict({"g_recpatcha_response": ""}),
             user_service=pretend.stub(),
             recaptcha_service=pretend.stub(
                 enabled=False,
@@ -507,7 +515,7 @@ def test_recaptcha_disabled(self):
 
     def test_recaptcha_required_error(self):
         form = forms.RegistrationForm(
-            data={"g_recaptcha_response": ""},
+            formdata=MultiDict({"g_recaptcha_response": ""}),
             user_service=pretend.stub(),
             recaptcha_service=pretend.stub(
                 enabled=True,
@@ -520,7 +528,7 @@ def test_recaptcha_required_error(self):
 
     def test_recaptcha_error(self):
         form = forms.RegistrationForm(
-            data={"g_recaptcha_response": "asd"},
+            formdata=MultiDict({"g_recaptcha_response": "asd"}),
             user_service=pretend.stub(),
             recaptcha_service=pretend.stub(
                 verify_response=pretend.raiser(recaptcha.RecaptchaError),
@@ -533,7 +541,7 @@ def test_recaptcha_error(self):
 
     def test_username_exists(self, pyramid_config):
         form = forms.RegistrationForm(
-            data={"username": "foo"},
+            formdata=MultiDict({"username": "foo"}),
             user_service=pretend.stub(
                 find_userid=pretend.call_recorder(lambda name: 1),
                 username_is_prohibited=lambda a: False,
@@ -553,7 +561,7 @@ def test_username_exists(self, pyramid_config):
 
     def test_username_prohibted(self, pyramid_config):
         form = forms.RegistrationForm(
-            data={"username": "foo"},
+            formdata=MultiDict({"username": "foo"}),
             user_service=pretend.stub(
                 username_is_prohibited=lambda a: True,
             ),
@@ -573,7 +581,7 @@ def test_username_prohibted(self, pyramid_config):
     @pytest.mark.parametrize("username", ["_foo", "bar_", "foo^bar"])
     def test_username_is_valid(self, username, pyramid_config):
         form = forms.RegistrationForm(
-            data={"username": username},
+            formdata=MultiDict({"username": username}),
             user_service=pretend.stub(
                 find_userid=pretend.call_recorder(lambda _: None),
                 username_is_prohibited=lambda a: False,
@@ -601,7 +609,7 @@ def test_password_strength(self):
         )
         for pwd, valid in cases:
             form = forms.RegistrationForm(
-                data={"new_password": pwd, "password_confirm": pwd},
+                formdata=MultiDict({"new_password": pwd, "password_confirm": pwd}),
                 user_service=pretend.stub(),
                 recaptcha_service=pretend.stub(
                     enabled=False,
@@ -614,7 +622,7 @@ def test_password_strength(self):
 
     def test_password_breached(self):
         form = forms.RegistrationForm(
-            data={"new_password": "password"},
+            formdata=MultiDict({"new_password": "password"}),
             user_service=pretend.stub(
                 find_userid=pretend.call_recorder(lambda _: None)
             ),
@@ -638,7 +646,7 @@ def test_password_breached(self):
 
     def test_name_too_long(self, pyramid_config):
         form = forms.RegistrationForm(
-            data={"full_name": "hello " * 50},
+            formdata=MultiDict({"full_name": "hello " * 50}),
             user_service=pretend.stub(
                 find_userid=pretend.call_recorder(lambda _: None)
             ),
@@ -703,7 +711,7 @@ def test_validate_username_or_email_with_none(self):
 class TestResetPasswordForm:
     def test_password_confirm_required_error(self):
         form = forms.ResetPasswordForm(
-            data={"password_confirm": ""},
+            formdata=MultiDict({"password_confirm": ""}),
             breach_service=pretend.stub(check_password=lambda pw, tags=None: False),
         )
 
@@ -712,13 +720,15 @@ def test_password_confirm_required_error(self):
 
     def test_passwords_mismatch_error(self, pyramid_config):
         form = forms.ResetPasswordForm(
-            data={
-                "new_password": "password",
-                "password_confirm": "mismatch",
-                "username": "username",
-                "full_name": "full_name",
-                "email": "email",
-            },
+            formdata=MultiDict(
+                {
+                    "new_password": "password",
+                    "password_confirm": "mismatch",
+                    "username": "username",
+                    "full_name": "full_name",
+                    "email": "email",
+                }
+            ),
             breach_service=pretend.stub(check_password=lambda pw, tags=None: False),
         )
 
@@ -734,13 +744,15 @@ def test_passwords_mismatch_error(self, pyramid_config):
     )
     def test_password_strength(self, password, expected):
         form = forms.ResetPasswordForm(
-            data={
-                "new_password": password,
-                "password_confirm": password,
-                "username": "username",
-                "full_name": "full_name",
-                "email": "email",
-            },
+            formdata=MultiDict(
+                {
+                    "new_password": password,
+                    "password_confirm": password,
+                    "username": "username",
+                    "full_name": "full_name",
+                    "email": "email",
+                }
+            ),
             breach_service=pretend.stub(check_password=lambda pw, tags=None: False),
         )
 
@@ -748,13 +760,15 @@ def test_password_strength(self, password, expected):
 
     def test_passwords_match_success(self):
         form = forms.ResetPasswordForm(
-            data={
-                "new_password": "MyStr0ng!shPassword",
-                "password_confirm": "MyStr0ng!shPassword",
-                "username": "username",
-                "full_name": "full_name",
-                "email": "email",
-            },
+            formdata=MultiDict(
+                {
+                    "new_password": "MyStr0ng!shPassword",
+                    "password_confirm": "MyStr0ng!shPassword",
+                    "username": "username",
+                    "full_name": "full_name",
+                    "email": "email",
+                }
+            ),
             breach_service=pretend.stub(check_password=lambda pw, tags=None: False),
         )
 
@@ -762,13 +776,15 @@ def test_passwords_match_success(self):
 
     def test_password_breached(self):
         form = forms.ResetPasswordForm(
-            data={
-                "new_password": "MyStr0ng!shPassword",
-                "password_confirm": "MyStr0ng!shPassword",
-                "username": "username",
-                "full_name": "full_name",
-                "email": "email",
-            },
+            formdata=MultiDict(
+                {
+                    "new_password": "MyStr0ng!shPassword",
+                    "password_confirm": "MyStr0ng!shPassword",
+                    "username": "username",
+                    "full_name": "full_name",
+                    "email": "email",
+                }
+            ),
             user_service=pretend.stub(
                 find_userid=pretend.call_recorder(lambda _: None)
             ),
@@ -803,8 +819,8 @@ def test_totp_secret_exists(self, pyramid_config):
         request = pretend.stub(remote_addr="1.2.3.4")
 
         form = forms.TOTPAuthenticationForm(
+            formdata=MultiDict({"totp_value": ""}),
             request=request,
-            data={"totp_value": ""},
             user_id=pretend.stub(),
             user_service=pretend.stub(get_user=get_user),
         )
@@ -813,7 +829,7 @@ def test_totp_secret_exists(self, pyramid_config):
 
         form = forms.TOTPAuthenticationForm(
             request=request,
-            data={"totp_value": "not_a_real_value"},
+            formdata=MultiDict({"totp_value": "not_a_real_value"}),
             user_id=pretend.stub(),
             user_service=pretend.stub(
                 check_totp_value=lambda *a: True, get_user=get_user
@@ -824,7 +840,7 @@ def test_totp_secret_exists(self, pyramid_config):
 
         form = forms.TOTPAuthenticationForm(
             request=request,
-            data={"totp_value": "1 2 3 4 5 6 7"},
+            formdata=MultiDict({"totp_value": "1 2 3 4 5 6 7"}),
             user_id=pretend.stub(),
             user_service=pretend.stub(
                 check_totp_value=lambda *a: True, get_user=get_user
@@ -838,8 +854,8 @@ def test_totp_secret_exists(self, pyramid_config):
             get_user=get_user,
         )
         form = forms.TOTPAuthenticationForm(
+            formdata=MultiDict({"totp_value": "123456"}),
             request=request,
-            data={"totp_value": "123456"},
             user_id=1,
             user_service=user_service,
         )
@@ -855,8 +871,8 @@ def test_totp_secret_exists(self, pyramid_config):
         ]
 
         form = forms.TOTPAuthenticationForm(
+            formdata=MultiDict({"totp_value": "123456"}),
             request=request,
-            data={"totp_value": "123456"},
             user_id=pretend.stub(),
             user_service=pretend.stub(
                 check_totp_value=lambda *a: True, get_user=get_user
@@ -866,7 +882,7 @@ def test_totp_secret_exists(self, pyramid_config):
 
         form = forms.TOTPAuthenticationForm(
             request=request,
-            data={"totp_value": " 1 2 3 4  5 6 "},
+            formdata=MultiDict({"totp_value": " 1 2 3 4  5 6 "}),
             user_id=pretend.stub(),
             user_service=pretend.stub(
                 check_totp_value=lambda *a: True, get_user=get_user
@@ -876,7 +892,7 @@ def test_totp_secret_exists(self, pyramid_config):
 
         form = forms.TOTPAuthenticationForm(
             request=request,
-            data={"totp_value": "123 456"},
+            formdata=MultiDict({"totp_value": "123 456"}),
             user_id=pretend.stub(),
             user_service=pretend.stub(
                 check_totp_value=lambda *a: True, get_user=get_user
@@ -1006,8 +1022,8 @@ def test_creation(self):
     def test_missing_value(self):
         request = pretend.stub()
         form = forms.RecoveryCodeAuthenticationForm(
+            formdata=MultiDict({"recovery_code_value": ""}),
             request=request,
-            data={"recovery_code_value": ""},
             user_id=pretend.stub(),
             user_service=pretend.stub(),
         )
@@ -1038,8 +1054,8 @@ def test_invalid_recovery_code(
             get_user=pretend.call_recorder(lambda userid: user),
         )
         form = forms.RecoveryCodeAuthenticationForm(
+            formdata=MultiDict({"recovery_code_value": "deadbeef00001111"}),
             request=request,
-            data={"recovery_code_value": "deadbeef00001111"},
             user_id=1,
             user_service=user_service,
         )
@@ -1059,8 +1075,8 @@ def test_valid_recovery_code(self, monkeypatch):
         request = pretend.stub(remote_addr="1.2.3.4")
         user = pretend.stub(id=pretend.stub(), username="foobar")
         form = forms.RecoveryCodeAuthenticationForm(
+            formdata=MultiDict({"recovery_code_value": "deadbeef00001111"}),
             request=request,
-            data={"recovery_code_value": "deadbeef00001111"},
             user_id=pretend.stub(),
             user_service=pretend.stub(
                 check_recovery_code=pretend.call_recorder(lambda *a, **kw: True),
@@ -1095,7 +1111,7 @@ def test_recovery_code_string_validation(
         user = pretend.stub(id=pretend.stub(), username="foobar")
         form = forms.RecoveryCodeAuthenticationForm(
             request=request,
-            data={"recovery_code_value": input_string},
+            formdata=MultiDict({"recovery_code_value": input_string}),
             user_id=pretend.stub(),
             user_service=pretend.stub(
                 check_recovery_code=pretend.call_recorder(lambda *a, **kw: True),
diff --git a/tests/unit/admin/views/test_banners.py b/tests/unit/admin/views/test_banners.py
index 29e81cbe9335..18586e6fdf29 100644
--- a/tests/unit/admin/views/test_banners.py
+++ b/tests/unit/admin/views/test_banners.py
@@ -218,13 +218,13 @@ def test_preview_banner(self, db_request):
 
 class TestBannerForm:
     def test_required_fields(self, banner_data):
-        form = views.BannerForm(data={})
+        form = views.BannerForm(formdata=MultiDict())
 
         assert form.validate() is False
         assert set(form.errors) == set(banner_data)
 
     def test_valid_data(self, banner_data):
-        form = views.BannerForm(data=banner_data)
+        form = views.BannerForm(formdata=MultiDict(banner_data))
         assert form.validate() is True
         data = form.data
         defaults = {
@@ -232,4 +232,7 @@ def test_valid_data(self, banner_data):
             "active": False,
             "link_label": Banner.DEFAULT_BTN_LABEL,
         }
+
+        # Mash the `end` into a date object to match the form's coerced result.
+        banner_data["end"] = datetime.date.fromisoformat(banner_data["end"])
         assert data == {**banner_data, **defaults}
diff --git a/tests/unit/admin/views/test_sponsors.py b/tests/unit/admin/views/test_sponsors.py
index 4a9fce60b45a..9e1baea092f2 100644
--- a/tests/unit/admin/views/test_sponsors.py
+++ b/tests/unit/admin/views/test_sponsors.py
@@ -260,29 +260,29 @@ def test_required_fields(self):
             assert field in form.errors
 
     def test_valid_data(self):
-        form = views.SponsorForm(data=self.data)
+        form = views.SponsorForm(formdata=MultiDict(self.data))
         assert form.validate() is True
 
     def test_white_logo_is_required_for_footer_display(self):
         self.data["footer"] = True
 
         # don't validate without logo
-        form = views.SponsorForm(data=self.data)
+        form = views.SponsorForm(formdata=MultiDict(self.data))
         assert form.validate() is False
         assert "white_logo" in form.errors
 
         self.data["white_logo_url"] = "http://domain.com/white-logo.jpg"
-        form = views.SponsorForm(data=self.data)
+        form = views.SponsorForm(formdata=MultiDict(self.data))
         assert form.validate() is True
 
     def test_white_logo_is_required_for_infra_display(self):
         self.data["infra_sponsor"] = True
 
         # don't validate without logo
-        form = views.SponsorForm(data=self.data)
+        form = views.SponsorForm(formdata=MultiDict(self.data))
         assert form.validate() is False
         assert "white_logo" in form.errors
 
         self.data["white_logo_url"] = "http://domain.com/white-logo.jpg"
-        form = views.SponsorForm(data=self.data)
+        form = views.SponsorForm(formdata=MultiDict(self.data))
         assert form.validate() is True
diff --git a/tests/unit/manage/test_forms.py b/tests/unit/manage/test_forms.py
index d13e071a0ad0..c29a0c6601e4 100644
--- a/tests/unit/manage/test_forms.py
+++ b/tests/unit/manage/test_forms.py
@@ -57,7 +57,7 @@ def test_validate_username_with_user(self):
         [
             ("", "Select role"),
             ("invalid", "Not a valid choice."),
-            (None, "Not a valid choice."),
+            (None, "Select role"),
         ],
     )
     def test_validate_role_name_fails(self, value, expected):
@@ -81,7 +81,7 @@ def test_creation(self):
     def test_email_exists_error(self, pyramid_config):
         user_id = pretend.stub()
         form = forms.AddEmailForm(
-            data={"email": "foo@bar.com"},
+            formdata=MultiDict({"email": "foo@bar.com"}),
             user_id=user_id,
             user_service=pretend.stub(find_userid_by_email=lambda _: user_id),
         )
@@ -95,7 +95,7 @@ def test_email_exists_error(self, pyramid_config):
 
     def test_email_exists_other_account_error(self, pyramid_config):
         form = forms.AddEmailForm(
-            data={"email": "foo@bar.com"},
+            formdata=MultiDict({"email": "foo@bar.com"}),
             user_id=pretend.stub(),
             user_service=pretend.stub(find_userid_by_email=lambda _: pretend.stub()),
         )
@@ -109,7 +109,7 @@ def test_email_exists_other_account_error(self, pyramid_config):
 
     def test_prohibited_email_error(self, pyramid_config):
         form = forms.AddEmailForm(
-            data={"email": "foo@bearsarefuzzy.com"},
+            formdata=MultiDict({"email": "foo@bearsarefuzzy.com"}),
             user_service=pretend.stub(find_userid_by_email=lambda _: None),
             user_id=pretend.stub(),
         )
@@ -148,7 +148,7 @@ def test_verify_totp_invalid(self, monkeypatch):
         monkeypatch.setattr(otp, "verify_totp", verify_totp)
 
         form = forms.ProvisionTOTPForm(
-            data={"totp_value": "123456"}, totp_secret=pretend.stub()
+            formdata=MultiDict({"totp_value": "123456"}), totp_secret=pretend.stub()
         )
         assert not form.validate()
         assert form.totp_value.errors.pop() == "Invalid TOTP code. Try again?"
@@ -158,7 +158,7 @@ def test_verify_totp_valid(self, monkeypatch):
         monkeypatch.setattr(otp, "verify_totp", verify_totp)
 
         form = forms.ProvisionTOTPForm(
-            data={"totp_value": "123456"}, totp_secret=pretend.stub()
+            formdata=MultiDict({"totp_value": "123456"}), totp_secret=pretend.stub()
         )
         assert form.validate()
 
@@ -182,10 +182,9 @@ def test_validate_confirm_password(self):
             ),
         )
         form = forms.DeleteTOTPForm(
-            username="username",
+            formdata=MultiDict({"username": "username", "password": "password"}),
             request=request,
             user_service=user_service,
-            password="password",
         )
 
         assert form.validate()
@@ -218,7 +217,7 @@ def test_verify_assertion_invalid_json(self):
         )
 
         form = forms.ProvisionWebAuthnForm(
-            data={"credential": "invalid json", "label": "fake label"},
+            formdata=MultiDict({"credential": "invalid json", "label": "fake label"}),
             user_service=user_service,
             user_id=pretend.stub(),
             challenge=pretend.stub(),
@@ -239,7 +238,7 @@ def test_verify_assertion_invalid(self):
             get_webauthn_by_label=pretend.call_recorder(lambda *a: None),
         )
         form = forms.ProvisionWebAuthnForm(
-            data={"credential": "{}", "label": "fake label"},
+            formdata=MultiDict({"credential": "{}", "label": "fake label"}),
             user_service=user_service,
             user_id=pretend.stub(),
             challenge=pretend.stub(),
@@ -255,7 +254,7 @@ def test_verify_label_missing(self):
             verify_webauthn_credential=lambda *a, **kw: pretend.stub()
         )
         form = forms.ProvisionWebAuthnForm(
-            data={"credential": "{}"},
+            formdata=MultiDict({"credential": "{}"}),
             user_service=user_service,
             user_id=pretend.stub(),
             challenge=pretend.stub(),
@@ -272,7 +271,7 @@ def test_verify_label_already_in_use(self):
             get_webauthn_by_label=pretend.call_recorder(lambda *a: pretend.stub()),
         )
         form = forms.ProvisionWebAuthnForm(
-            data={"credential": "{}", "label": "fake label"},
+            formdata=MultiDict({"credential": "{}", "label": "fake label"}),
             user_service=user_service,
             user_id=pretend.stub(),
             challenge=pretend.stub(),
@@ -290,7 +289,7 @@ def test_creates_validated_credential(self):
             get_webauthn_by_label=pretend.call_recorder(lambda *a: None),
         )
         form = forms.ProvisionWebAuthnForm(
-            data={"credential": "{}", "label": "fake label"},
+            formdata=MultiDict({"credential": "{}", "label": "fake label"}),
             user_service=user_service,
             user_id=pretend.stub(),
             challenge=pretend.stub(),
@@ -323,7 +322,7 @@ def test_validate_label_not_in_use(self):
             get_webauthn_by_label=pretend.call_recorder(lambda *a: None)
         )
         form = forms.DeleteWebAuthnForm(
-            data={"label": "fake label"},
+            formdata=MultiDict({"label": "fake label"}),
             user_service=user_service,
             user_id=pretend.stub(),
         )
@@ -337,7 +336,7 @@ def test_creates_webauthn_attribute(self):
             get_webauthn_by_label=pretend.call_recorder(lambda *a: fake_webauthn)
         )
         form = forms.DeleteWebAuthnForm(
-            data={"label": "fake label"},
+            formdata=MultiDict({"label": "fake label"}),
             user_service=user_service,
             user_id=pretend.stub(),
         )
@@ -363,7 +362,7 @@ def test_creation(self):
 
     def test_validate_description_missing(self):
         form = forms.CreateMacaroonForm(
-            data={"token_scope": "scope:user"},
+            formdata=MultiDict({"token_scope": "scope:user"}),
             user_id=pretend.stub(),
             macaroon_service=pretend.stub(),
             project_names=pretend.stub(),
@@ -374,7 +373,7 @@ def test_validate_description_missing(self):
 
     def test_validate_description_in_use(self):
         form = forms.CreateMacaroonForm(
-            data={"description": "dummy", "token_scope": "scope:user"},
+            formdata=MultiDict({"description": "dummy", "token_scope": "scope:user"}),
             user_id=pretend.stub(),
             macaroon_service=pretend.stub(
                 get_macaroon_by_description=lambda *a: pretend.stub()
@@ -387,7 +386,7 @@ def test_validate_description_in_use(self):
 
     def test_validate_token_scope_missing(self):
         form = forms.CreateMacaroonForm(
-            data={"description": "dummy"},
+            formdata=MultiDict({"description": "dummy"}),
             user_id=pretend.stub(),
             macaroon_service=pretend.stub(get_macaroon_by_description=lambda *a: None),
             project_names=pretend.stub(),
@@ -398,7 +397,9 @@ def test_validate_token_scope_missing(self):
 
     def test_validate_token_scope_unspecified(self):
         form = forms.CreateMacaroonForm(
-            data={"description": "dummy", "token_scope": "scope:unspecified"},
+            formdata=MultiDict(
+                {"description": "dummy", "token_scope": "scope:unspecified"}
+            ),
             user_id=pretend.stub(),
             macaroon_service=pretend.stub(get_macaroon_by_description=lambda *a: None),
             project_names=pretend.stub(),
@@ -412,7 +413,7 @@ def test_validate_token_scope_unspecified(self):
     )
     def test_validate_token_scope_invalid_format(self, scope):
         form = forms.CreateMacaroonForm(
-            data={"description": "dummy", "token_scope": scope},
+            formdata=MultiDict({"description": "dummy", "token_scope": scope}),
             user_id=pretend.stub(),
             macaroon_service=pretend.stub(get_macaroon_by_description=lambda *a: None),
             project_names=pretend.stub(),
@@ -423,7 +424,9 @@ def test_validate_token_scope_invalid_format(self, scope):
 
     def test_validate_token_scope_invalid_project(self):
         form = forms.CreateMacaroonForm(
-            data={"description": "dummy", "token_scope": "scope:project:foo"},
+            formdata=MultiDict(
+                {"description": "dummy", "token_scope": "scope:project:foo"}
+            ),
             user_id=pretend.stub(),
             macaroon_service=pretend.stub(get_macaroon_by_description=lambda *a: None),
             project_names=["bar"],
@@ -434,7 +437,7 @@ def test_validate_token_scope_invalid_project(self):
 
     def test_validate_token_scope_valid_user(self):
         form = forms.CreateMacaroonForm(
-            data={"description": "dummy", "token_scope": "scope:user"},
+            formdata=MultiDict({"description": "dummy", "token_scope": "scope:user"}),
             user_id=pretend.stub(),
             macaroon_service=pretend.stub(get_macaroon_by_description=lambda *a: None),
             project_names=pretend.stub(),
@@ -444,7 +447,9 @@ def test_validate_token_scope_valid_user(self):
 
     def test_validate_token_scope_valid_project(self):
         form = forms.CreateMacaroonForm(
-            data={"description": "dummy", "token_scope": "scope:project:foo"},
+            formdata=MultiDict(
+                {"description": "dummy", "token_scope": "scope:project:foo"}
+            ),
             user_id=pretend.stub(),
             macaroon_service=pretend.stub(get_macaroon_by_description=lambda *a: None),
             project_names=["foo"],
@@ -478,7 +483,7 @@ def test_validate_macaroon_id_invalid(self):
             remote_addr="1.2.3.4", banned=pretend.stub(by_ip=lambda ip_address: False)
         )
         form = forms.DeleteMacaroonForm(
-            data={"macaroon_id": pretend.stub(), "password": "password"},
+            formdata=MultiDict({"macaroon_id": pretend.stub(), "password": "password"}),
             request=request,
             macaroon_service=macaroon_service,
             user_service=user_service,
@@ -499,10 +504,15 @@ def test_validate_macaroon_id(self):
             remote_addr="1.2.3.4", banned=pretend.stub(by_ip=lambda ip_address: False)
         )
         form = forms.DeleteMacaroonForm(
-            data={"macaroon_id": pretend.stub(), "password": "password"},
+            formdata=MultiDict(
+                {
+                    "macaroon_id": pretend.stub(),
+                    "username": "username",
+                    "password": "password",
+                }
+            ),
             request=request,
             macaroon_service=macaroon_service,
-            username="username",
             user_service=user_service,
         )
 
diff --git a/warehouse/accounts/forms.py b/warehouse/accounts/forms.py
index abbe4c8a0761..b81272c53d05 100644
--- a/warehouse/accounts/forms.py
+++ b/warehouse/accounts/forms.py
@@ -48,7 +48,7 @@
 
 
 class UsernameMixin:
-    username = wtforms.StringField(validators=[wtforms.validators.DataRequired()])
+    username = wtforms.StringField(validators=[wtforms.validators.InputRequired()])
 
     def validate_username(self, field):
         userid = self.user_service.find_userid(field.data)
@@ -62,7 +62,7 @@ def validate_username(self, field):
 class TOTPValueMixin:
     totp_value = wtforms.StringField(
         validators=[
-            wtforms.validators.DataRequired(),
+            wtforms.validators.InputRequired(),
             wtforms.validators.Regexp(
                 rf"^ *([0-9] *){{{TOTP_LENGTH}}}$",
                 message=_(
@@ -75,13 +75,13 @@ class TOTPValueMixin:
 
 
 class WebAuthnCredentialMixin:
-    credential = wtforms.StringField(wtforms.validators.DataRequired())
+    credential = wtforms.StringField(wtforms.validators.InputRequired())
 
 
 class RecoveryCodeValueMixin:
     recovery_code_value = wtforms.StringField(
         validators=[
-            wtforms.validators.DataRequired(),
+            wtforms.validators.InputRequired(),
             wtforms.validators.Regexp(
                 rf"^ *([0-9a-f] *){{{2*RECOVERY_CODE_BYTES}}}$",
                 message=_(
@@ -96,7 +96,7 @@ class RecoveryCodeValueMixin:
 class NewUsernameMixin:
     username = wtforms.StringField(
         validators=[
-            wtforms.validators.DataRequired(),
+            wtforms.validators.InputRequired(),
             wtforms.validators.Length(
                 max=50, message=_("Choose a username with 50 characters or less.")
             ),
@@ -131,7 +131,7 @@ def validate_username(self, field):
 class PasswordMixin:
     password = wtforms.PasswordField(
         validators=[
-            wtforms.validators.DataRequired(),
+            wtforms.validators.InputRequired(),
             wtforms.validators.Length(
                 max=MAX_PASSWORD_SIZE,
                 message=_("Password too long."),
@@ -180,7 +180,7 @@ def validate_password(self, field):
 class NewPasswordMixin:
     new_password = wtforms.PasswordField(
         validators=[
-            wtforms.validators.DataRequired(),
+            wtforms.validators.InputRequired(),
             wtforms.validators.Length(
                 max=MAX_PASSWORD_SIZE,
                 message=_("Password too long."),
@@ -193,7 +193,7 @@ class NewPasswordMixin:
 
     password_confirm = wtforms.PasswordField(
         validators=[
-            wtforms.validators.DataRequired(),
+            wtforms.validators.InputRequired(),
             wtforms.validators.Length(
                 max=MAX_PASSWORD_SIZE,
                 message=_("Password too long."),
@@ -208,8 +208,8 @@ class NewPasswordMixin:
     # PasswordStrengthValidator of the new_password field, to ensure that the
     # newly set password doesn't contain any of them
     full_name = wtforms.StringField()  # May be empty
-    username = wtforms.StringField(validators=[wtforms.validators.DataRequired()])
-    email = wtforms.StringField(validators=[wtforms.validators.DataRequired()])
+    username = wtforms.StringField(validators=[wtforms.validators.InputRequired()])
+    email = wtforms.StringField(validators=[wtforms.validators.InputRequired()])
 
     def __init__(self, *args, breach_service, **kwargs):
         super().__init__(*args, **kwargs)
@@ -227,7 +227,7 @@ def validate_new_password(self, field):
 class NewEmailMixin:
     email = wtforms.fields.EmailField(
         validators=[
-            wtforms.validators.DataRequired(),
+            wtforms.validators.InputRequired(),
             wtforms.validators.Regexp(
                 r".+@.+\..+", message=_("The email address isn't valid. Try again.")
             ),
@@ -423,13 +423,13 @@ class ReAuthenticateForm(PasswordMixin, forms.Form):
     __params__ = ["username", "password", "next_route", "next_route_matchdict"]
 
     username = wtforms.fields.HiddenField(
-        validators=[wtforms.validators.DataRequired()]
+        validators=[wtforms.validators.InputRequired()]
     )
     next_route = wtforms.fields.HiddenField(
-        validators=[wtforms.validators.DataRequired()]
+        validators=[wtforms.validators.InputRequired()]
     )
     next_route_matchdict = wtforms.fields.HiddenField(
-        validators=[wtforms.validators.DataRequired()]
+        validators=[wtforms.validators.InputRequired()]
     )
 
     def __init__(self, *args, user_service, **kwargs):
@@ -472,7 +472,7 @@ def validate_recovery_code_value(self, field):
 
 class RequestPasswordResetForm(forms.Form):
     username_or_email = wtforms.StringField(
-        validators=[wtforms.validators.DataRequired()]
+        validators=[wtforms.validators.InputRequired()]
     )
 
     def __init__(self, *args, user_service, **kwargs):
diff --git a/warehouse/accounts/views.py b/warehouse/accounts/views.py
index 2f7db82b372f..d3301d1f7466 100644
--- a/warehouse/accounts/views.py
+++ b/warehouse/accounts/views.py
@@ -29,6 +29,7 @@
 from pyramid.view import view_config, view_defaults
 from sqlalchemy.exc import NoResultFound
 from webauthn.helpers import bytes_to_base64url
+from webob.multidict import MultiDict
 
 from warehouse.accounts import REDIRECT_FIELD_NAME
 from warehouse.accounts.forms import (
@@ -559,10 +560,12 @@ def register(request, _form_class=RegistrationForm):
 
     # the form contains an auto-generated field from recaptcha with
     # hyphens in it. make it play nice with wtforms.
-    post_body = {key.replace("-", "_"): value for key, value in request.POST.items()}
+    post_body = MultiDict(
+        {key.replace("-", "_"): value for key, value in request.POST.items()}
+    )
 
     form = _form_class(
-        data=post_body,
+        formdata=post_body,
         user_service=user_service,
         recaptcha_service=recaptcha_service,
         breach_service=breach_service,
diff --git a/warehouse/admin/views/banners.py b/warehouse/admin/views/banners.py
index f90aa0cec5d7..e7df2e57d29e 100644
--- a/warehouse/admin/views/banners.py
+++ b/warehouse/admin/views/banners.py
@@ -148,18 +148,18 @@ class BannerForm(Form):
     name = wtforms.fields.StringField(
         validators=[
             wtforms.validators.Length(max=100),
-            wtforms.validators.DataRequired(),
+            wtforms.validators.InputRequired(),
         ],
     )
     text = wtforms.fields.StringField(
         validators=[
             wtforms.validators.Length(max=280),
-            wtforms.validators.DataRequired(),
+            wtforms.validators.InputRequired(),
         ],
     )
     link_url = wtforms.fields.StringField(
         validators=[
-            wtforms.validators.DataRequired(),
+            wtforms.validators.InputRequired(),
             URIValidator(),
         ]
     )
@@ -179,4 +179,4 @@ class BannerForm(Form):
     active = wtforms.fields.BooleanField(
         validators=[wtforms.validators.Optional()], default=False
     )
-    end = wtforms.fields.DateField(validators=[wtforms.validators.DataRequired()])
+    end = wtforms.fields.DateField(validators=[wtforms.validators.InputRequired()])
diff --git a/warehouse/admin/views/sponsors.py b/warehouse/admin/views/sponsors.py
index c9da0ce7cf07..b2d3451c166d 100644
--- a/warehouse/admin/views/sponsors.py
+++ b/warehouse/admin/views/sponsors.py
@@ -30,7 +30,7 @@ class SponsorForm(Form):
     name = wtforms.fields.StringField(
         validators=[
             wtforms.validators.Length(max=100),
-            wtforms.validators.DataRequired(),
+            wtforms.validators.InputRequired(),
         ],
     )
     service = wtforms.fields.StringField(
@@ -39,7 +39,7 @@ class SponsorForm(Form):
 
     link_url = wtforms.fields.StringField(
         validators=[
-            wtforms.validators.DataRequired(),
+            wtforms.validators.InputRequired(),
             URIValidator(),
         ]
     )
diff --git a/warehouse/admin/views/users.py b/warehouse/admin/views/users.py
index 5c06843a1616..163295c00e24 100644
--- a/warehouse/admin/views/users.py
+++ b/warehouse/admin/views/users.py
@@ -74,7 +74,7 @@ def user_list(request):
 
 
 class EmailForm(forms.Form):
-    email = wtforms.fields.EmailField(validators=[wtforms.validators.DataRequired()])
+    email = wtforms.fields.EmailField(validators=[wtforms.validators.InputRequired()])
     primary = wtforms.fields.BooleanField()
     verified = wtforms.fields.BooleanField()
     public = wtforms.fields.BooleanField()
diff --git a/warehouse/forklift/legacy.py b/warehouse/forklift/legacy.py
index c16c1d7d922f..729d8cfb680a 100644
--- a/warehouse/forklift/legacy.py
+++ b/warehouse/forklift/legacy.py
@@ -421,7 +421,7 @@ class MetadataForm(forms.Form):
     metadata_version = wtforms.StringField(
         description="Metadata-Version",
         validators=[
-            wtforms.validators.DataRequired(),
+            wtforms.validators.InputRequired(),
             wtforms.validators.AnyOf(
                 # Note: This isn't really Metadata 2.0, however bdist_wheel
                 #       claims it is producing a Metadata 2.0 metadata when in
@@ -436,7 +436,7 @@ class MetadataForm(forms.Form):
     name = wtforms.StringField(
         description="Name",
         validators=[
-            wtforms.validators.DataRequired(),
+            wtforms.validators.InputRequired(),
             wtforms.validators.Regexp(
                 PROJECT_NAME_RE,
                 re.IGNORECASE,
@@ -450,7 +450,7 @@ class MetadataForm(forms.Form):
     version = wtforms.StringField(
         description="Version",
         validators=[
-            wtforms.validators.DataRequired(),
+            wtforms.validators.InputRequired(),
             wtforms.validators.Regexp(
                 r"^(?!\s).*(?<!\s)$",
                 message="Can't have leading or trailing whitespace.",
@@ -526,7 +526,7 @@ class MetadataForm(forms.Form):
     pyversion = wtforms.StringField(validators=[wtforms.validators.Optional()])
     filetype = wtforms.StringField(
         validators=[
-            wtforms.validators.DataRequired(),
+            wtforms.validators.InputRequired(),
             wtforms.validators.AnyOf(
                 ["bdist_egg", "bdist_wheel", "sdist"], message="Use a known file type."
             ),
diff --git a/warehouse/forms.py b/warehouse/forms.py
index 1529fe0bf7cb..8b36226d88df 100644
--- a/warehouse/forms.py
+++ b/warehouse/forms.py
@@ -11,7 +11,7 @@
 # limitations under the License.
 
 from wtforms import Form as BaseForm, StringField
-from wtforms.validators import DataRequired, StopValidation, ValidationError
+from wtforms.validators import InputRequired, StopValidation, ValidationError
 from zxcvbn import zxcvbn
 
 from warehouse.i18n import KNOWN_LOCALES
@@ -124,7 +124,7 @@ def __init__(self, *args, db, **kwargs):
 class SetLocaleForm(Form):
     __params__ = ["locale_id"]
 
-    locale_id = StringField(validators=[DataRequired(message="Missing locale ID")])
+    locale_id = StringField(validators=[InputRequired(message="Missing locale ID")])
 
     def validate_locale_id(self, field):
         if field.data not in KNOWN_LOCALES.keys():
diff --git a/warehouse/locale/messages.pot b/warehouse/locale/messages.pot
index f0a619bb8480..ada718c24b40 100644
--- a/warehouse/locale/messages.pot
+++ b/warehouse/locale/messages.pot
@@ -1,10 +1,10 @@
-#: warehouse/views.py:140
+#: warehouse/views.py:141
 msgid ""
 "Two-factor authentication must be enabled on your account to perform this"
 " action."
 msgstr ""
 
-#: warehouse/views.py:265
+#: warehouse/views.py:266
 msgid "Locale updated"
 msgstr ""
 
@@ -100,216 +100,216 @@ msgstr ""
 msgid "No user found with that username or email"
 msgstr ""
 
-#: warehouse/accounts/views.py:99
+#: warehouse/accounts/views.py:100
 msgid ""
 "There have been too many unsuccessful login attempts. You have been "
 "locked out for {}. Please try again later."
 msgstr ""
 
-#: warehouse/accounts/views.py:116
+#: warehouse/accounts/views.py:117
 msgid ""
 "Too many emails have been added to this account without verifying them. "
 "Check your inbox and follow the verification links. (IP: ${ip})"
 msgstr ""
 
-#: warehouse/accounts/views.py:128
+#: warehouse/accounts/views.py:129
 msgid ""
 "Too many password resets have been requested for this account without "
 "completing them. Check your inbox and follow the verification links. (IP:"
 " ${ip})"
 msgstr ""
 
-#: warehouse/accounts/views.py:268 warehouse/accounts/views.py:332
-#: warehouse/accounts/views.py:334 warehouse/accounts/views.py:361
-#: warehouse/accounts/views.py:363 warehouse/accounts/views.py:429
+#: warehouse/accounts/views.py:269 warehouse/accounts/views.py:333
+#: warehouse/accounts/views.py:335 warehouse/accounts/views.py:362
+#: warehouse/accounts/views.py:364 warehouse/accounts/views.py:430
 msgid "Invalid or expired two factor login."
 msgstr ""
 
-#: warehouse/accounts/views.py:326
+#: warehouse/accounts/views.py:327
 msgid "Already authenticated"
 msgstr ""
 
-#: warehouse/accounts/views.py:405
+#: warehouse/accounts/views.py:406
 msgid "Successful WebAuthn assertion"
 msgstr ""
 
-#: warehouse/accounts/views.py:461 warehouse/manage/views/__init__.py:816
+#: warehouse/accounts/views.py:462 warehouse/manage/views/__init__.py:816
 msgid "Recovery code accepted. The supplied code cannot be used again."
 msgstr ""
 
-#: warehouse/accounts/views.py:547
+#: warehouse/accounts/views.py:548
 msgid ""
 "New user registration temporarily disabled. See https://pypi.org/help"
 "#admin-intervention for details."
 msgstr ""
 
-#: warehouse/accounts/views.py:679
+#: warehouse/accounts/views.py:682
 msgid "Expired token: request a new password reset link"
 msgstr ""
 
-#: warehouse/accounts/views.py:681
+#: warehouse/accounts/views.py:684
 msgid "Invalid token: request a new password reset link"
 msgstr ""
 
-#: warehouse/accounts/views.py:683 warehouse/accounts/views.py:786
-#: warehouse/accounts/views.py:886 warehouse/accounts/views.py:1059
+#: warehouse/accounts/views.py:686 warehouse/accounts/views.py:789
+#: warehouse/accounts/views.py:889 warehouse/accounts/views.py:1062
 msgid "Invalid token: no token supplied"
 msgstr ""
 
-#: warehouse/accounts/views.py:687
+#: warehouse/accounts/views.py:690
 msgid "Invalid token: not a password reset token"
 msgstr ""
 
-#: warehouse/accounts/views.py:692
+#: warehouse/accounts/views.py:695
 msgid "Invalid token: user not found"
 msgstr ""
 
-#: warehouse/accounts/views.py:703
+#: warehouse/accounts/views.py:706
 msgid "Invalid token: user has logged in since this token was requested"
 msgstr ""
 
-#: warehouse/accounts/views.py:721
+#: warehouse/accounts/views.py:724
 msgid ""
 "Invalid token: password has already been changed since this token was "
 "requested"
 msgstr ""
 
-#: warehouse/accounts/views.py:754
+#: warehouse/accounts/views.py:757
 msgid "You have reset your password"
 msgstr ""
 
-#: warehouse/accounts/views.py:782
+#: warehouse/accounts/views.py:785
 msgid "Expired token: request a new email verification link"
 msgstr ""
 
-#: warehouse/accounts/views.py:784
+#: warehouse/accounts/views.py:787
 msgid "Invalid token: request a new email verification link"
 msgstr ""
 
-#: warehouse/accounts/views.py:790
+#: warehouse/accounts/views.py:793
 msgid "Invalid token: not an email verification token"
 msgstr ""
 
-#: warehouse/accounts/views.py:799
+#: warehouse/accounts/views.py:802
 msgid "Email not found"
 msgstr ""
 
-#: warehouse/accounts/views.py:802
+#: warehouse/accounts/views.py:805
 msgid "Email already verified"
 msgstr ""
 
-#: warehouse/accounts/views.py:820
+#: warehouse/accounts/views.py:823
 msgid "You can now set this email as your primary address"
 msgstr ""
 
-#: warehouse/accounts/views.py:824
+#: warehouse/accounts/views.py:827
 msgid "This is your primary address"
 msgstr ""
 
-#: warehouse/accounts/views.py:829
+#: warehouse/accounts/views.py:832
 msgid "Email address ${email_address} verified. ${confirm_message}."
 msgstr ""
 
-#: warehouse/accounts/views.py:882
+#: warehouse/accounts/views.py:885
 msgid "Expired token: request a new organization invitation"
 msgstr ""
 
-#: warehouse/accounts/views.py:884
+#: warehouse/accounts/views.py:887
 msgid "Invalid token: request a new organization invitation"
 msgstr ""
 
-#: warehouse/accounts/views.py:890
+#: warehouse/accounts/views.py:893
 msgid "Invalid token: not an organization invitation token"
 msgstr ""
 
-#: warehouse/accounts/views.py:894
+#: warehouse/accounts/views.py:897
 msgid "Organization invitation is not valid."
 msgstr ""
 
-#: warehouse/accounts/views.py:903
+#: warehouse/accounts/views.py:906
 msgid "Organization invitation no longer exists."
 msgstr ""
 
-#: warehouse/accounts/views.py:956
+#: warehouse/accounts/views.py:959
 msgid "Invitation for '${organization_name}' is declined."
 msgstr ""
 
-#: warehouse/accounts/views.py:1021
+#: warehouse/accounts/views.py:1024
 msgid "You are now ${role} of the '${organization_name}' organization."
 msgstr ""
 
-#: warehouse/accounts/views.py:1055
+#: warehouse/accounts/views.py:1058
 msgid "Expired token: request a new project role invitation"
 msgstr ""
 
-#: warehouse/accounts/views.py:1057
+#: warehouse/accounts/views.py:1060
 msgid "Invalid token: request a new project role invitation"
 msgstr ""
 
-#: warehouse/accounts/views.py:1063
+#: warehouse/accounts/views.py:1066
 msgid "Invalid token: not a collaboration invitation token"
 msgstr ""
 
-#: warehouse/accounts/views.py:1067
+#: warehouse/accounts/views.py:1070
 msgid "Role invitation is not valid."
 msgstr ""
 
-#: warehouse/accounts/views.py:1082
+#: warehouse/accounts/views.py:1085
 msgid "Role invitation no longer exists."
 msgstr ""
 
-#: warehouse/accounts/views.py:1115
+#: warehouse/accounts/views.py:1118
 msgid "Invitation for '${project_name}' is declined."
 msgstr ""
 
-#: warehouse/accounts/views.py:1183
+#: warehouse/accounts/views.py:1186
 msgid "You are now ${role} of the '${project_name}' project."
 msgstr ""
 
-#: warehouse/accounts/views.py:1401 warehouse/accounts/views.py:1421
-#: warehouse/accounts/views.py:1556 warehouse/manage/views/__init__.py:1225
+#: warehouse/accounts/views.py:1404 warehouse/accounts/views.py:1424
+#: warehouse/accounts/views.py:1559 warehouse/manage/views/__init__.py:1225
 #: warehouse/manage/views/__init__.py:1244
 msgid ""
 "Trusted publishers are temporarily disabled. See https://pypi.org/help"
 "#admin-intervention for details."
 msgstr ""
 
-#: warehouse/accounts/views.py:1435
+#: warehouse/accounts/views.py:1438
 msgid ""
 "You must have a verified email in order to register a pending trusted "
 "publisher. See https://pypi.org/help#openid-connect for details."
 msgstr ""
 
-#: warehouse/accounts/views.py:1448
+#: warehouse/accounts/views.py:1451
 msgid "You can't register more than 3 pending trusted publishers at once."
 msgstr ""
 
-#: warehouse/accounts/views.py:1464 warehouse/manage/views/__init__.py:1263
+#: warehouse/accounts/views.py:1467 warehouse/manage/views/__init__.py:1263
 msgid ""
 "There have been too many attempted trusted publisher registrations. Try "
 "again later."
 msgstr ""
 
-#: warehouse/accounts/views.py:1478 warehouse/manage/views/__init__.py:1277
+#: warehouse/accounts/views.py:1481 warehouse/manage/views/__init__.py:1277
 msgid "The trusted publisher could not be registered"
 msgstr ""
 
-#: warehouse/accounts/views.py:1497
+#: warehouse/accounts/views.py:1500
 msgid ""
 "This trusted publisher has already been registered. Please contact PyPI's"
 " admins if this wasn't intentional."
 msgstr ""
 
-#: warehouse/accounts/views.py:1533
+#: warehouse/accounts/views.py:1536
 msgid "Registered a new publishing publisher to create "
 msgstr ""
 
-#: warehouse/accounts/views.py:1570 warehouse/accounts/views.py:1583
-#: warehouse/accounts/views.py:1590
+#: warehouse/accounts/views.py:1573 warehouse/accounts/views.py:1586
+#: warehouse/accounts/views.py:1593
 msgid "Invalid publisher ID"
 msgstr ""
 
-#: warehouse/accounts/views.py:1596
+#: warehouse/accounts/views.py:1599
 msgid "Removed trusted publisher for project "
 msgstr ""
 
diff --git a/warehouse/manage/forms.py b/warehouse/manage/forms.py
index 197092aa6a90..6eefec2314cf 100644
--- a/warehouse/manage/forms.py
+++ b/warehouse/manage/forms.py
@@ -40,7 +40,7 @@ class RoleNameMixin:
     role_name = wtforms.SelectField(
         "Select role",
         choices=[("", "Select role"), ("Maintainer", "Maintainer"), ("Owner", "Owner")],
-        validators=[wtforms.validators.DataRequired(message="Select role")],
+        validators=[wtforms.validators.InputRequired(message="Select role")],
     )
 
 
@@ -49,13 +49,13 @@ class TeamProjectRoleNameMixin:
         "Select permissions",
         choices=[("", "Select role"), ("Maintainer", "Maintainer"), ("Owner", "Owner")],
         coerce=lambda string: TeamProjectRoleType(string) if string else None,
-        validators=[wtforms.validators.DataRequired(message="Select role")],
+        validators=[wtforms.validators.InputRequired(message="Select role")],
     )
 
 
 class UsernameMixin:
     username = wtforms.StringField(
-        validators=[wtforms.validators.DataRequired(message="Specify username")]
+        validators=[wtforms.validators.InputRequired(message="Specify username")]
     )
 
     def validate_username(self, field):
@@ -212,7 +212,7 @@ class DeleteWebAuthnForm(forms.Form):
 
     label = wtforms.StringField(
         validators=[
-            wtforms.validators.DataRequired(message="Specify a device name"),
+            wtforms.validators.InputRequired(message="Specify a device name"),
             wtforms.validators.Length(
                 max=64, message=("Label must be 64 characters or less")
             ),
@@ -238,7 +238,7 @@ class ProvisionWebAuthnForm(WebAuthnCredentialMixin, forms.Form):
 
     label = wtforms.StringField(
         validators=[
-            wtforms.validators.DataRequired(message="Specify a label"),
+            wtforms.validators.InputRequired(message="Specify a label"),
             wtforms.validators.Length(
                 max=64, message=("Label must be 64 characters or less")
             ),
@@ -293,7 +293,7 @@ def __init__(self, *args, user_id, macaroon_service, project_names, **kwargs):
 
     description = wtforms.StringField(
         validators=[
-            wtforms.validators.DataRequired(message="Specify a token name"),
+            wtforms.validators.InputRequired(message="Specify a token name"),
             wtforms.validators.Length(
                 max=100, message="Description must be 100 characters or less"
             ),
@@ -301,7 +301,7 @@ def __init__(self, *args, user_id, macaroon_service, project_names, **kwargs):
     )
 
     token_scope = wtforms.StringField(
-        validators=[wtforms.validators.DataRequired(message="Specify the token scope")]
+        validators=[wtforms.validators.InputRequired(message="Specify the token scope")]
     )
 
     def validate_description(self, field):
@@ -347,7 +347,7 @@ class DeleteMacaroonForm(UsernameMixin, PasswordMixin, forms.Form):
     __params__ = ["confirm_password", "macaroon_id"]
 
     macaroon_id = wtforms.StringField(
-        validators=[wtforms.validators.DataRequired(message="Identifier required")]
+        validators=[wtforms.validators.InputRequired(message="Identifier required")]
     )
 
     def __init__(self, *args, macaroon_service, user_service, **kwargs):
@@ -381,14 +381,14 @@ class OrganizationRoleNameMixin:
             ("Billing Manager", "Billing Manager"),
         ],
         coerce=lambda string: OrganizationRoleType(string) if string else None,
-        validators=[wtforms.validators.DataRequired(message="Select role")],
+        validators=[wtforms.validators.InputRequired(message="Select role")],
     )
 
 
 class OrganizationNameMixin:
     name = wtforms.StringField(
         validators=[
-            wtforms.validators.DataRequired(
+            wtforms.validators.InputRequired(
                 message="Specify organization account name"
             ),
             wtforms.validators.Length(
@@ -487,7 +487,7 @@ class TransferOrganizationProjectForm(forms.Form):
         "Select organization",
         choices=[("", "Select organization")],
         validators=[
-            wtforms.validators.DataRequired(message="Select organization"),
+            wtforms.validators.InputRequired(message="Select organization"),
         ],
     )
 
@@ -538,7 +538,7 @@ class SaveOrganizationForm(forms.Form):
 
     display_name = wtforms.StringField(
         validators=[
-            wtforms.validators.DataRequired(message="Specify your organization name"),
+            wtforms.validators.InputRequired(message="Specify your organization name"),
             wtforms.validators.Length(
                 max=100,
                 message=_(
@@ -550,7 +550,7 @@ class SaveOrganizationForm(forms.Form):
     )
     link_url = wtforms.URLField(
         validators=[
-            wtforms.validators.DataRequired(message="Specify your organization URL"),
+            wtforms.validators.InputRequired(message="Specify your organization URL"),
             wtforms.validators.Length(
                 max=400,
                 message=_(
@@ -566,7 +566,7 @@ class SaveOrganizationForm(forms.Form):
     )
     description = wtforms.TextAreaField(
         validators=[
-            wtforms.validators.DataRequired(
+            wtforms.validators.InputRequired(
                 message="Specify your organization description"
             ),
             wtforms.validators.Length(
@@ -582,7 +582,7 @@ class SaveOrganizationForm(forms.Form):
         choices=[("Company", "Company"), ("Community", "Community")],
         coerce=OrganizationType,
         validators=[
-            wtforms.validators.DataRequired(message="Select organization type"),
+            wtforms.validators.InputRequired(message="Select organization type"),
         ],
     )
 
@@ -609,7 +609,7 @@ class SaveTeamForm(forms.Form):
 
     name = wtforms.StringField(
         validators=[
-            wtforms.validators.DataRequired(message="Specify team name"),
+            wtforms.validators.InputRequired(message="Specify team name"),
             wtforms.validators.Length(
                 max=50,
                 message=_("Choose a team name with 50 characters or less."),
diff --git a/warehouse/oidc/forms.py b/warehouse/oidc/forms.py
index 26b927cac3fe..8f13c9906519 100644
--- a/warehouse/oidc/forms.py
+++ b/warehouse/oidc/forms.py
@@ -29,7 +29,7 @@ class GitHubPublisherBase(forms.Form):
 
     owner = wtforms.StringField(
         validators=[
-            wtforms.validators.DataRequired(
+            wtforms.validators.InputRequired(
                 message=_("Specify GitHub repository owner (username or organization)"),
             ),
         ]
@@ -37,7 +37,7 @@ class GitHubPublisherBase(forms.Form):
 
     repository = wtforms.StringField(
         validators=[
-            wtforms.validators.DataRequired(message=_("Specify repository name")),
+            wtforms.validators.InputRequired(message=_("Specify repository name")),
             wtforms.validators.Regexp(
                 _VALID_GITHUB_REPO, message=_("Invalid repository name")
             ),
@@ -46,7 +46,7 @@ class GitHubPublisherBase(forms.Form):
 
     workflow_filename = wtforms.StringField(
         validators=[
-            wtforms.validators.DataRequired(message=_("Specify workflow filename"))
+            wtforms.validators.InputRequired(message=_("Specify workflow filename"))
         ]
     )
 
@@ -170,7 +170,7 @@ class PendingGitHubPublisherForm(GitHubPublisherBase):
 
     project_name = wtforms.StringField(
         validators=[
-            wtforms.validators.DataRequired(message=_("Specify project name")),
+            wtforms.validators.InputRequired(message=_("Specify project name")),
             wtforms.validators.Regexp(
                 PROJECT_NAME_RE, message=_("Invalid project name")
             ),
@@ -199,7 +199,7 @@ class DeletePublisherForm(forms.Form):
 
     publisher_id = wtforms.StringField(
         validators=[
-            wtforms.validators.DataRequired(message=_("Specify a publisher ID")),
+            wtforms.validators.InputRequired(message=_("Specify a publisher ID")),
             wtforms.validators.UUID(message=_("Publisher must be specified by ID")),
         ]
     )
diff --git a/warehouse/views.py b/warehouse/views.py
index 4292217c5dee..5cdb9b00cf46 100644
--- a/warehouse/views.py
+++ b/warehouse/views.py
@@ -40,6 +40,7 @@
 from sqlalchemy import func
 from sqlalchemy.sql import exists, expression
 from trove_classifiers import deprecated_classifiers, sorted_classifiers
+from webob.multidict import MultiDict
 
 from warehouse.accounts import REDIRECT_FIELD_NAME
 from warehouse.accounts.models import User
@@ -246,7 +247,7 @@ def index(request):
 )
 def locale(request):
     try:
-        form = SetLocaleForm(locale_id=request.GET.getone("locale_id"))
+        form = SetLocaleForm(MultiDict({"locale_id": request.GET.getone("locale_id")}))
     except KeyError:
         raise HTTPBadRequest("Invalid amount of locale_id parameters provided")