.xsession-errors file contains Tor Browser related warning (Debian Linux)

A forensic analysis of the Tor Browser Bundle on Debian Linux showed that the file ~/.xsession-errors contains a Tor Browser related warning: _Window manager warning: Buggy client sent a NET_ACTIVE_WINDOW message with a timestamp of 0 for 0x3800089 (Tor Browse)”. It is worth noting that a file named ~/.xsession-errors.old could also exist.