For the *unwashed masses* tabs is the only positive feature of FF.
Well, I suppose a study could be done to determine this, but based purely on my interactions with others, that's not the case.
Early-on, those who might be considered among the "unwashed masses" I knew were actually confused by tabs. And I'll have to admit I was initially resistant to the idea until I became accustomed to it and realized how much easier it made my browsing life. (I'd used Opera before encountering Firefox and wasn't particularly impressed by tabs.) One client I had way back when, for example, never used the tabs, but he liked certain extensions and used them a lot.
You said it yourself with your comment about AdBlock.
I agree with your bottom line, though. I've never thought that one browser being declared superior to all the others was a desirable goal. I use four different browsers actually, Firefox being most common. They've all improved a great deal in the last several years, and I think Firefox's success (not just its technical success but its success in infiltrating the browser market itself) has had a great influence on that.
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