I have also noticed that PLS crashes when I change the connections from one server to another. I cannot give you a rule, but the fact is that it crashes.
On version 14 this happened more often than in version 15.0.3. I'm sorry that I cannot give you more details.

This issue known for many years. Log off/Log on new base resolves it.
More connections you have before logon to new base (without log off), so more chance to crash.
Pay attention to sessions window after changing connection. All your sessions relogin to new server, and I don't know why. Maybe it is a cause...

I have exactly the same problem. I can't debug the program at all. The whole thing gets stuck. There is a CrossThread error in the Windows event log! I debugged your program using x32dbg. And among other things, you have an error in SetThreadName , Unknown name. this error causes the program to hang often. Unfortunately, it still says Executing... and I wait an infinite time, I have to kill the process. We have purchased this program and I need it to work. I tried all versions from 12 -> 15. Unfortunately, I have Windows 11. And it happened after the last update, the update is KB5021234, I tried to uninstall the update but the problem was not solved. I think the problem is with you and you will have to make better compatibility.If you want contact me at edie.6b@gmail.com. I'll give you a crash dump, logs, whatever.

Is there any news about stability / performance fix we may expect? Especially the freezes are really a pain to deal with everyday. Also the "initializing..." when changing tab connection and "executing..." that doesn't go away unless I close the tab. In my experience after that PLS is in an error state, so close and restart required.

Is this thread still monitored or should I start a new thread? Not sure if this is a Windows 11 update incompatibility or an error introduced in a later version of PSD. In both cases it would be nice if this were sorted out. The freezes are quite often and very annoying.

Thank you, this fix made it a lot better!
After switching to three 4K monitors, alt-tabbing and moving the PL/SQL Developer window between screens became very slow. Making multi-tasking quite tedious.

As a potato, I use a lot of different apps, but I have only experienced these problems to a significant degree with PL/SQL Developer.
Which I find quite sad, because other than the tedium of the freezes and the occasional crashes (and even cleared workspaces!), it is a great piece of software.

"For me performance improved and freezes seem gone after: Setting "None" for Light "
Yes, it is better, but the PL/SQL Dev. version 14 is far more better than 15 or 16

"Making multi-tasking quite tedious."
Yes. When I press alt-tab, the PL/SQL Developer ui popup hints appear after I switch to an other application .
It does not happens, when I use "None" theme.