[wlesieutre]

Tree style tabs addon makes huge numbers of tabs useable, you really rethink the whole tab workflow.

For logging into sites like gmail and Facebook, consider using Containers https://support.mozilla.org/en-US/kb/how-facebook-container-...

[Izkata]

Hoo yeah, before TreeStyleTabs, I limited myself to somewhere around 30-40 just because there wasn't room to see everything.

Nowadays I'm up somewhere around 300 and it's not a big deal, because they self-organize into related groups that are expandable/collapsible.