Dear Maintainer, When a window is fullscreen changing to another window (for example using the keyboard shortcut alt+tab) stops the cinnamon panel from appearing. I've attached an image of the issue to this bug report and there is also a bug report upstream with more details. The easiest way to reproduce this is to have two unmaximized windows then press F11 to make one of the windows fullscreen then pressing alt+tab. Upstream bug report: https://github.com/linuxmint/cinnamon/issues/10954