Hyperlinkbutton not working with uri of type mailto:someone@somewhere.com

[ArturRuta]

Describe the bug

Hyperlinkbutton not working with uri of type mailto:someone@somewhere.com

Steps to reproduce the bug

Steps to reproduce the behavior:
Place an hyperlinkbutton like the one below in any page. Run the application and click it.

Expected behavior
Default Windows Email Client should open
Note: Have checked in windows settinds that a default windows application is defined and also this kind of uri does work when when launched from a browser navigation bar

Screenshots

Version Info

NuGet package version:

Microsoft.WinUI 3.0.0-preview4.210210.4

Windows app type:

UWP	Win32
No	Yes

Windows 10 version	Saw the problem?
Insider Build (xxxxx)
October 2020 Update (19042)	Yes
May 2020 Update (19041)
November 2019 Update (18363)
May 2019 Update (18362)
October 2018 Update (17763)
April 2018 Update (17134)
Fall Creators Update (16299)
Creators Update (15063)

Device form factor	Saw the problem?
Desktop	Yes
Xbox
Surface Hub
IoT

Additional context
When run from the debugguer i see report of exceptions thrown although nothing is seen in the application

[StephenLPeters]

@Austin-Lamb I'm not sure this would be winui's fault. Thoughts?

[ArturRuta]

Well I do think it something in winui or in the way it talks to underlying components because:

• there's a defaul application for handling emails (as per windows10 settings)
• entering an url of the type mailto: in a browser does open the default email application
• also a c# call like the one below does open the default mail application with the expected contents (that's the temporary bypass i'm launching from a button while this gets sorted)
  await Windows.System.Launcher.LaunchUriAsync(new Uri("mailto:someone@somewhere.com?subject=Suggestion&body=Suggestion proposal
• There's no code behind manipulating events from the hyperlinkbutton
• It happens all the time and its straightforward to reproduce
• And also I feel it's rather suspicious to see the exceptions I pasted above any type the hyperlinkbutton is tried with an url ot the type mailto. This doesn't happen when the url is of the type http://www.microsoft.con

[BluVeneziano]

Same behaviour with NuGet package version:

Microsoft.ProjectReunion.WinUI 0.5.0

[savian-net]

Also, not working with file:// links. Works using Windows.System.Launcher.LaunchUriAsync(link); on Click event