In the time before Chrome, Firefox market share grew in part because of how aggressively Google and the rest of the web advertised for them. However, that market share peaked and shrunk after Chrome was released; Google shifted _all_ of their advertising from Firefox for Chrome.
There is nothing wrong with having an irrelevant share of the market. Most software I use has a market share in the 0-2% range.
However, Mozilla screwed up quite badly because their response to being pushed out of the mainstream was to gut everything that would have made them an interesting niche player. Their niche could have been "OK, this isn't Chrome but you get an IRC client and a bunch of crazy capabilities that are fun at lan parties. We'll train the next generation of devs by giving them cool capabilities to experiment with!". Instead, the niche is the worse version of Chrome.
> metrics have shown over and over again that people didn't use XUL addons
Now the metrics show people don't use Firefox. Funny thing, life. I think it was a bad time to make a metric-driven decision.
I'd be happy with a Firefox that didn't have stupid UI mistakes like making it impossible to tell which tab is selected. Or which didn't lose all my tabs in a crash. Getting the basics right matters.
How do you know?
And yet, the anecedata here on HN suggests that you are probably surrounded of those people that did use them. Deciding that suddenly the longstanding demographic of Firefox users - tech people - are no longer relevant to the company strategy was a shitty move, and it drove them away.
I am aware there is some mucking around that I could perform to maybe get it working, but it probably involves changing some settings that I'm not sure I should.
Throwaway since I used to work at Mozilla:
You are 100% wrong in your analysis, metrics have shown over and over again that people didn't use XUL addons (even if you add the people disabling telemetry).
The real culprits to Mozilla's market share downtrend are:
1. Google started advertising Chrome on every single property they own (e.g. Google search) and made deals to pre-install Chrome on new computers. On mobile devices with Android it's even worse: if the default is good enough, why change?
2. During that time Firefox was playing catch-up: for a long time it was multiple times slower and crashier (and still is to a small extent) due to its older architecture. Meanwhile, Google with 2-3x more engineers on Chrome can deliver a better browser and pump out new w3c standards every month.
3. The Mozilla leadership reacted too late, too slow and with the failure of Firefox OS they've become risk averse and they'd rather become irrelevant than dead.