https://github.com/python-pillow/Pillow/actions/runs/9108593264/job/25039692144#step:5:225

src/display.c: In function 'windowCallback':
src/display.c:508:20: warning: variable 'current_threadstate' set but not used [-Wunused-but-set-variable]
508 | PyThreadState *current_threadstate;
| ^~~~~~~~~~~~~~~~~~~

Looking at windowCallback(), I think this should be used at the end of the function to restore the original thread state.