In this table it says that there is no stream isolation in Tor Browser in Whonix workstation but I do not understand as Tor Browser will use separate SOCKS auth for every first party domain which will give stream isolation.
whonix org/wiki/Other_Operating_Systems#Security_Comparison:Whonix.E2.84.A2-Download-Workstation_vs.Whonix-Custom-Workstation.E2.84.A2