You can bookmark a single tab via the right-click context menu in three sidebar and you can open all synced tab as tabs in Firefox and then use bookmark all tabs. I'm not aware of a way to bookmark all synced tabs directly.

I see, opened the 400+ tabs. Ah, the sound of computer fans at full speed, hoping the browser wouldn't crash. I was lucky this time.

As I was bookmarking the tabs, I didn't really need to actually open them. Is there a way to just get the tabs on the tab bar without opening them?

Thanks

Unless something has changed, I don't think Firefox has a built-in feature to "Bookmark All Sync'd Tabs" (listed in the sidebar).

At someone's request, I posted a script you can run in Firefox's Browser Console (Ctrl+Shift+J) to generate an HTML Export-style bookmark file of the list of tabs. In case you want to take a look (you need to change a setting to enable the command line in the Browser Console before you run this the first time):

Export Synced Tabs List to "bookmarks.html" file (Browser Console script)

jscher2000: Nice, thank you. I ran the script and copied pasted the content of the resulting bookmark file to a browser bookmark file and imported it in Firefox (may take time if you have a huge bookmark file). They showed up in the library window just as other bookmarks, so this worked the way I hoped it would.

Dropa: You're talking about working on individual tabs here? This is cumbersome with many tabs.

At someone's request, I posted a script you can run in Firefox's Browser Console (Ctrl+Shift+J) to generate an HTML Export-style bookmark file of the list of tabs.

Works like a charm for me too! Thank you!