Dialog and Popup display issues in certain screen sharing scenarios

[Awsmolak]

When trying to "share window" in MS Teams, there is a lot of weird issues with display of dialogs/views with dialoghost. I assume it has to do with rendering of transparencies.

Note: This issue only occurs when sharing in "window" mode, not when sharing the entire screen. Additionally, I have noticed that if I try to share my window from an app running in the VS Debugger the entire window just displays as black box to other meeting participants. I have not done enough testing to be 100% sure it's related, but it smells like it...

Here is an example of what a participant sees with dialogs:

And with popups: Note: the tooltip as well as the popup menu exhibit the issue

I did find a thread on SO from someone seeing a similar issue: https://stackoverflow.com/questions/65514472/transparent-child-window-renders-as-black-when-screen-sharing-main-window-on-mic#comment124517453_65514472

[Awsmolak]

Of note: I just tested this with a colleague, different machines with vastly different display setups and GPUs. Both in .net4.8 and .net5.

[Erapchu]

Did you tried to set background property to #00000000? Background="#00000000"