Sudden green screen, then crash

My MBA (OS 11.4) occasionally (maybe about once every two weeks) will, at a random moment, suddenly green screen, crash, and restart. Nothing specific seems to trigger it; it's happened when using Safari or saving a file in Photoshop. I'm not sure if this is related to my ongoing issue of my MBA's performance degrading over a 5-7 day cycle until it's restarted. Any idea what could cause this?