Dear Maintainer,

When running applications in Cage inside Sway, the video output occassionally
freezes up completely. Resizing Cage appears to resume the output.

I am not sure what triggers this but it happens often. When running `cage kitty`,
sometimes the output will freeze before the shell prompt is even
displayed.

I have also observed this issue with `cage foot` and `cage firefox`, so
it's unlikely to be specific to the application running inside Cage.