Attempt to use outline or shadow effects results in black borders.
Steps to reproduce:
1) Open attached project
2) Open GameScreen.uxml
3) Select the ".action-button:hover" selector
4) Modify some of the Text Shadow or Outline properties
5) Activate preview and hover the "Continue" button

I have also observed some variations:
- The shadow might work at first, but with the wrong color. But then it gets corrupted when changing the outline.
- Sometimes the issues are not identical between game view and UI Builder.
- The thickness of the shadow might be right sometimes, but there is no "gradient" to zero opacity (it looks like a solid outline)

Reproduced with: 2021.2.0b10
changeset: 528997:2e1b2da87b7b
branch: 2021.2/staging
date: Tue Aug 24 09:29:24 2021 +0000

Reproduced with: 2022.1.0a7
changeset: 530045:1be0ffb18df1
branch: trunk
date: Sat Aug 21 19:52:39 2021 +0000