Re-checking with the crash-handler on, the entries are empty, with:
$ od -b ~/.r/crashpad_database/settings.dat
0000000 163 144 120 103 001 000 000 000 001 000 000 000 000 000 000 000
0000020 000 000 000 000 000 000 000 000 322 326 133 036 153 121 272 113
0000040 207 220 222 164 031 027 372 014
0000050
Typically, the whole RStudio window goes blank apart from the top menu line, is unresponsive, and has to be killed, for example from the system monitor. To check the running session interface, use e.g.:
loginctl show-session 2 -p Type