I am developing webbased applications using ESP32-wifi. To test the result I need the browser to see the result. Now I make changes, upload and go to the browser hit F5 and see the resulting changes. However from time to time I happen to hit F5 in the wrong environment, Arduino IDE 2.0 RC5, and the content of the IDE disappears, the sketch titel is shown to be "Index.html". The IDE might recover after a while or it may not. A restart of the IDE is then required to get back to normal.
I think the F5 issue must have the same cause, since I see it was introduced at the same time via the update of the Eclipse Theia framework the Arduino IDE is built on.
I added a comment on that bug report about the F5 issue you reported: