I got a similar error on Linux Mint Debian Edition:Hmmm... update doesn't work for me. On Fedora 32, I get:
X Error of failed request: BadLength (poly request too large or internal Xlib length error)
Major opcode of failed request: 0 ()
Serial number of failed request: 175
Current serial number in output stream: 175
X Error of failed request: BadLength (poly request too large or internal Xlib length error)
Major opcode of failed request: 18 (X_ChangeProperty)
Serial number of failed request: 180
Current serial number in output stream: 180