Hi,
I have several large tab groups with hundreds of tabs. Everything was working fine, but after the recent firefox update (89?), when I go to the tab groups view, firefox just totally freezes, so I have to terminate it. If I open firefox by clicking on a link in an external program, the link opens fine (I will have two tabs, the opened page and the panorama view), but going back to the panorama view freezes everything again.
The only way I can continue to use the tabs I have opened previously is to open a new link as described above and then from the address bar find a tab that is already open in a tab group. If I click on that, I can use that specific tab group just fine.