About dialog changes tooltip theme from Light to Dark

[strangebit]

Windows Terminal version

1.18.2822.0

Windows build number

10.0.19045.0

Other Software

No response

Steps to reproduce

Use a Dark application theme. Open a new Terminal window and take note of the tooltip theming. Open the About dialog and close it and then recheck tooltip theming.

Expected Behavior

No response

Actual Behavior

I noticed this behaviour today, and I can consistently reproduce it. When I open a new Terminal window, the tooltips for that window are Light themed up until I open the About dialog, and then they become Dark themed (but only for that window). You can see what I mean in the following video:

TooltipTheming.mp4

In my settings.json, I'm using this custom Dark theme (the purpose is just to allow me to hide the close buttons on the tabs):

"theme": "dark_no-close-button",
"themes": 
[
    {
        "name": "dark_no-close-button",
        "tab": 
        {
            "background": "terminalBackground",
            "showCloseButton": "never",
            "unfocusedBackground": "#00000000"
        },
        "tabRow": 
        {
            "background": "#2E2E2EFF",
            "unfocusedBackground": "#333333FF"
        },
        "window": 
        {
            "applicationTheme": "dark",
            "useMica": false
        }
    }
]

It happens when I just use "theme": "dark" or "theme": "legacyDark" as well though.

Here are my Windows colour settings:

[zadjii-msft]

LMAO this is hilarious. Yep. That makes sense. We don't do the themingLambda to update the tooltip themes until the About dialog gets opened and goes and updates all "popup" things. Incredible.

I bed we could just do the theming lambda on startup? Though, I dunno if the popup XAML root exists at that time. It might not get created until the first popup is shown, and I dunno if we'll always know when a popup is opened. Hmm.