Found two related bugs but neither mentions multi-edit and symptoms not exactly the same (eg one says the visible highlighted file changes correctly but it doesn't in my case with multiple files.)
https://bugs.launchpad.net/ubuntu/+source/thunar/+bug/1311926
https://bugs.launchpad.net/ubuntu/+source/thunar/+bug/1172529
Found two related bugs but neither mentions multi-edit and symptoms not exactly the same (eg one says the visible highlighted file changes correctly but it doesn't in my case with multiple files.)
https:/ /bugs.launchpad .net/ubuntu/ +source/ thunar/ +bug/1311926
https:/ /bugs.launchpad .net/ubuntu/ +source/ thunar/ +bug/1172529