I have Ubuntu 22.04 and for me after trying out the tips from
did not worked (or it was a combination of the above and below).
What instead worked was starting IDE from terminal with parameter: rstudio --no-sandbox
I'm not sure what are (if any) drawbacks but the gui rendered correctly and I could work in IDE without any issues (importing libraries, working on .R files, stepping through the code, snippets etc).
Source of the solution which worked for me: https://computingforgeeks.com/how-to-install-r-and-rstudio-on-ubuntu-debian-mint/
Hope this helps.