Stop! Do not install this flatpak version. Go over to JetBrains and install their tarball, instead. What the OPs say is true. The flatpak version has lots of very subtle issues that will frustrate you with setting up your projects and stop your programs from working correctly. We have all learned this the hardway, with lots of wasted hours trying to solve issues that can only/maybe be fixed with kludges and weird workarounds. Intellij is a great program, but the flatpak installation is not worth the time and trouble.
There is an issue with reaching all executables outside the flatpak-environment, for example with getting svn to work: https://stackoverflow.com/questions/60318660/flatpak-intellij-idea-problem-with-subversion-executable but also when you want to integrate your Java-program with a compiled c-program that depends on *.o files that can't be reached from the flatpak-environment. I finally installed IntelliJ without flatpak by just downloading it straight from Jetbrains.
no problems runs flawlessly!
Ich kann die IDE nicht benutzen, wenn ich sie von hier aus herunterlade. Es kommt immer ein Fehler und ich weiß nicht, wie ich den beheben kann. Wenn ich IDEA von snap herunterlade, lässt sie sich zumindest ordnungsgemäß starten. Wie ich damit zurecht komme, muss ich erst noch testen.
The IDE itself is absolutely great, but the flatpak version is a real pain. The various file choser dialogs in settings etc. do not show all files, you cannot use a local docker instance, because Unix Sockets are not accessible, propsed updates cannot be installed and so on, and so on. After multiple annyoyances, I downloaded the version from jetbrains.com and all problems were gone.