Created attachment 8991 Diff file for src/main_window.c I modified Ristretto so that the mouse cursor will disappear after 1 second of inactivity while in fullscreen mode (then reappear when the mouse is moved again). I only modified src/main_window.c, so I have attached a patch file for the differences between the current file (from commit a368e8d8f260cb59e5a33c4631f34cee7e1dba03), and my version. I hope this feature is useful.
Igor referenced this bugreport in commit 520b15bedc6be80d1f05b8ae04096e5d939ab69a Hide the cursor while inactive in fullscreen mode https://git.xfce.org/apps/ristretto/commit?id=520b15bedc6be80d1f05b8ae04096e5d939ab69a
Thank you for the proposal and the patch! I've committed a slightly modified version of the patch.