Comment # 9 on bug 1137203 from Reinhard Max

I already had a try at debugging it together with Dominik two days ago and this
is what we found out so far:

Tk has two ways of specifying the size of a font: A positive number specifies
it in pixels and a negative number specifies it in points. A size specified in
points gets translated into pixels internally depending on the DPI resolution
of the display.

On the affected setup font sizes given in points get translated into 0 pixels
and that's why the text is not visible.

We also noticed that this setup runs on Xwayland and tried it with a second X
session with a "normal" X server, which didn't have the problem. But we weren't
sure if it was really caused by wayland or if there were any additional
differences between the two sessions that might have caused it.

Thanks for the instructions on booting the image locally, this will help me a
lot in narrowing it down further.