Shell stays blank

### Windows Terminal version

1.24.10621.0

### Windows build number

10.0.26220.0

### Other Software

I suppose I got this version through Windows Update.
I'm on **Windows 11 Insider Preview Feature Update (26220.7934)**

The terminal app starts, but the shells stay blank (black). no cursor, nothing.
There seem to be a flicker in the pane within the Terminal.
That's the case no matter which shell I start (WSL, Powershell, CMD).

Powershell host, started without terminal works fine. starting WSL from there works fine too.
Not sure where to start for the bug report though, but happy to provide more info with guidance.

Settings panel works fine, and I clicked "reset to factory settings" but that did not help. same behavior.

I'll try to update to a more recent build, and maybe to an older build to see if that solves the problem.

### Steps to reproduce

N/A

### Expected Behavior

shell appears

### Actual Behavior

no shell

Begin with the Windows Terminal app and compare launching WSL, PowerShell, and CMD, noting the blank pane and flicker. Check whether changing Windows or Terminal builds affects the behavior, as the report proposes; done means a shell appears with a cursor and usable output.

Written by the indexing model from the issue text.