I wrote an Fvwm configuration yesterday. It worked fine on a computer with an ATI graphics card.
This morning I installed the configuration on my desktop, which uses an old nVidia card (a Quadro NVS 280). On that computer it is completely unusable, because the fonts have become invisible in various places. Particularly in the taskbar and menus, fonts do not appear at all.
I tried taking a screenshot of it, but all the fonts showed up fine in the screenshot.
This happens both with the nouveau driver, and with the legacy nv driver. I haven't tried the nVidia proprietary driver yet, because it is unusable on this hardware - its 2D performance is much worse than nv or nouveau, to the point of unusability.
Can anyone tell me what the problem might be?
Edit: for now I've worked around the problem by using bitmap fonts, which are rendered okay; but this is not really a good solution.