RStudio UI is unstable (windows and panels appear and disappear all the time)

I’ve opened RStudio after a few days without using it, and the UI has become unusable. See here for a video of what happens.

I have tried to downgrade the package but the problem persists, so I think it’s more likely to be some other package that has been updated recently. But I have no clue.

RStudio’s log file reports a recurring message:

2021-12-07T11:21:58.384919Z [rsession-*myname*] WARNING No memory control group found in /proc/self/cgroup; LOGGED FROM: std::__cxx11::string rstudio::core::system::{anonymous}::getMemoryCgroup() src/cpp/core/system/LinuxResources.cpp:335

I don’t know if that’s related to my problem, but I don’t know where else to start from.