Until at least around 1 month ago it was possbile to open all tabs from another device's firefox. You could go to the Synced Tabs Sidebar, right-click the other device's name and click something named along the lines of "open all tabs". When I tried to do this today, I noticed that the "normal" way to the Sync-menu via |||\ symbol doesn't work anymore and I at least found out that I could get there using via the firefox account. I can send a (single) tab to another device and I can see the list of the sync'ed tabs of a computer, but it is no longer possible to right-click that device's name and thereby getting to the "open all tabs" option. After this was - seemingly? - patched out, is there any other way left to do this or was there any new way implemented? thx