Alexandr Miloslavskiy

Try changing screen's DPI to 200% in your Linux settings and see what the new "magic" constant would be.

I would suspect that SWT calls some kind of `redraw()`, or maybe it sets different size with `SetWindowPos()`, which causes Tooltip to endlessly repaint.

I meant `Control.redraw()` which calls `OS.RedrawWindow()`, but it could aslo be `OS.InvalidateRect()`, showing and hiding, etc. Anything that could trigger tooltip to repaint.

Please reduce this to an SWT snippet and I could have a look and figure why these "endless" events are sent. It's quite likely that there will be an SWT...

Curios, so some special conditions are needed. Probably the problem lurks there. If time allows, I'll try to extract snippet. It's not that I have too much time to look...

Not reproducible for me with Eclipse 2022-12:  Curiously for the first time tooltip is shown,it shows at different DPI.

I also tried a number of other DPI combinations and the problem is still not reproducible: 100/150%, 100/175%, 125/100%, 150/100%, 150/125%

I also tried these steps on Win10 and also didn't reproduce. I'm beginning to suspect 3rd party software.

If you're willing to do some debugging with native debugger, I could explain how. It's going to be simple enough to just follow the steps.

Unfortunately I don't have the time to investigate.