Firefox occasionally not rendering its own window when opened

Solution 1:

In the case where you have only Nvidia card, you can try the solution in the other answer.

Turns out it has something to do in the case when you disable the Nvidia card and use integrated graphics. Firefox seems to be trying to render through the disabled GPU. To fix add this to your .profile:

if ! grep -w -q nvidia <(lsmod) ; then export
__EGL_VENDOR_LIBRARY_FILENAMES="/usr/share/glvnd/egl_vendor.d/50_mesa.json"
fi

logout then login and the problem is solved.

Source