Confirmed crash on 126.96.36.199952, but only when use 'gbak' utility (with services call).
As of fbsvcmgr, it works correct and reports error: Unknown switch "res_user_all_space".
Output when use gbak is:
gbak:unknown switch "USER_ALL_SPACE"
gbak: ERROR:Unable to complete network request to host "localhost".
gbak: ERROR: Error reading data from the connection.
gbak:Exiting before completion due to errors
Checked on WI-V188.8.131.52962 - works OK.
No test needed for 3.0 thus only stub code present here in 'firebird_version': '3.0' section.