Hello there, I'm having a similar issue, where everytime I load a scene my cursor disappears, the only way to get it back is to hold left-alt and left-click. After that if i press left_click again to moove the camera the cursor disappears again and I'm unable to move the camera or perform any action in general, it looks like the cursor get stuck and I cannot move it! I can provide a clip if needed!
I'm using 1.5.9