Hello! Please report this bug to the developers. When I first launch Firefox after turning on my computer, the window title bar and buttons in the upper right corner (like "Minimize," "Minimize to Window," and "Close") sometimes disappear. If I minimize the browser via the bottom taskbar and then restore it, these buttons and the title bar appear. I'm using Windows 10 x64, with a screen resolution of 2560x1440 (scaled to 125%, but I don't think this has anything to do with the scale or resolution, as other browsers (Opera, Edge) don't have these title bar issues). See screenshots at the links: https://imgur.com/a/Hbc9yvE (There are two screenshots: 1 - with the window title and buttons (as it should be), 2 - when the window title and buttons disappear) I've noticed that if I let Windows sit for a while after turning on the PC (2-3 minutes) and then launch Firefox, the problem with the disappearing title bar and buttons seems to disappear. Apparently, Firefox doesn't have time to load properly after Windows loads, and if I launch Firefox almost immediately after Windows loads, the problem described above occurs. And when the OS sits for 2-3 minutes, Firefox apparently loads all its services and processes normally and then works normally, without this error. Firefox ver.: 150.0.3. This bug was also discussed on the forum by some other users, and they are also experiencing this bug: https://forum.mozilla-russia.org/viewtopic.php?pid=818805