Fix: Fixed issue where new tab icon disappears when window is smaller than 640px

[ferrariofilippo]

Resolved / Related Issues

• Were these changes approved in an issue or discussion with the project maintainers? In order to prevent extra work, feature requests and changes to the codebase must be approved before the pull request will be reviewed. This prevents extra work for the contributors and maintainers.
  Closes Bug: New tab icon disappears when window is smaller than 640 pixels #11797

Changes

• Now New Tab button is always visible
• Fixes a bug where you couldn't close tabs (using x button) when window was smaller than 640px

Validation
How did you test these changes?

• Did you build the app and test your changes?
• Did you check for accessibility? You can use Accessibility Insights for this.
• Did you remove any strings from the en-us resource file?
  • Did you search the solution to see if the string is still being used?
• Did you implement any design changes to an existing feature?
  • Was this change approved?
• Are there any other steps that were used to validate these changes?
  1. NOTE To test changes you have to build Files as release or comment out line 128 of DragZoneHelper.cs (XAML toolbar may interfere with taps)
  2. Resize the window so that it it smaller than 640px
  3. Try to create a tab using the + button

[yaira2]

Thank you