Paolo,
Thank you for your report. I just ran few tests with MyEclipse 2022 on Ubuntu 22.04 and could not reproduce the problem with the perspectives.
Can you please restart the IDE, switch to a new workspace and check if you can replicate it? If yes, then please share the screenshot of the changes you have made to the perspective to help us replicate the problem at our end. Also share with us the .log file located at workspace dir/.metadata/.log to help us check for any internal errors logged. Rename the extension to .txt and attach it here.
–Swapna
Genuitec Support