Pressing and dragging no longer work when using Firefox on a Windows touch device. Tested with Firefox 69 on our Windows 10 laptop. Also note bug 7395 which might be related.
Firefox 66 works fine, so this does seem to be the same issue as bug 7395. Let's wait for that to be fixed and retest.
Tested a Windows 11 laptop with touch using Firefox 134 against a 4.17.0 server. I was able to drag around applications with press+drag using touch. Seems to have been fixed. Closing.