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assembly: 0.074

Alt-TAB minimizes a full screen key-grabbed SDL window
Description of problem:
I was made aware of a case where a qemu seems to respond to a keyboard event `Alt+Tab` that isn't meant for it.

When running in "SDL + full-screen + keys being grabbed by the guest" (see steps to reproduce below) one would expect `Alt+Tab` to do nothing on the host. But it does minimize the qemu window.

This does not happen if:
- using GTK instead of SDL
- not being in full-screen mode

No error message or warning appears while this happens.
Steps to reproduce:
You do not need and workload to run inside qemu for this

1. `qemu-system-x86_64 -display sdl`
2. Get your key grabbed: `click inside the window`
3. Go full screen: `Alt+Ctrl+F`
4. Press `Alt+Tab`
5. Expected: nothing, Experienced: window minimizes

Note: it even is reproducible if running the qemu binary from another system through SSH with X11 forwarding.

P.S.
I haven't had a chance yet to try qemu 7.0 from git, but will in a bit.
It is easy enough to reproduce that I considered it worth filing without.
For the start it would be great to hear if others see that as well or not. In case of the latter we'd have to compare library versions (currently I use sdl 2.0.20+dfsg-2build1).