However, Opera supported an MDI interface before it supported tabs, and if you count that it may have supported multiple browser windows within one MDI window even earlier, which could be said to be a form of tabs.
Everything depends on how you define "tabs", as usual.
And in a HN thread a couple weeks ago someone posted about how “everyone” switched to Chrome because it invented tabs, if you want to know what today’s web developers think.
I loved tabs in Galeon, it's the only browser I remembering having it at the time, but I probably didn't try Opera. I was sad when Galeon went away (or removed tabs? I don't recall) and I couldn't find another browser with tab support for a while. Again, I may have overlooked Opera :)
Galeon was also the only usable Linux browser having a native look on Gnome (Epiphany was the other one, but I remember it having more difficulty with a lot of sites).
It embedded the Mozilla engine (which was a supported use case back then, before Firefox) but launched a lot faster. Usable on a 200Mhz machine at least.
