Widget condition with unexpected character not preventing from saving

[devhn]

Preconditions

1. Magento 2.1

Steps to reproduce

1. Install Magento from community branch.
2. Create a new widget via admin (Content -->Widgets)
3. Widget type: Catalog Products List
4. Layout update: Specific category
5. Widget options (conditions): Set product as new from date. Entered value: {TODAY}

Expected result

1. It should display an error about unexpected character and not allow to save the widget

Actual result

1. Upon saving the widget it display and error on frontend (attached)
2. When trying to edit the widget it displays an error on backend (attached)

This happens when using {TODAY} as a time value and not actual formatted date.
Is the {TODAY} parameter obsolete? And will there be an option to delete the widget from the administration in the future as currently there is no selection options with actions within the Widgets section?

errors.zip

[piotrekkaminski]

internal issue MAGETWO-53440