I have recently upgrade my Eclipse installation from 2020-06 (4.16) to 2020-09 (4.17) using the recommended way. After restart and while opening the same workspace I use for years, the close button/icon is missing for some views when they are selected
This seems to be a known problem. However, closing the view and reopening it (as suggested on that page) doesn't work for me - the icon/button is still missing. I have also tried closing the view, restarting Eclipse, re-opening the view, and also while starting Eclipse using the -clean argument. This didn't help either.
Interestingly enough, for some views the icon/button is shown.
What else can be done to get the icon/button back?