If people are curious, all the stats for Wikimedia properties are here: https://analytics.wikimedia.org/dashboards/browsers/#desktop...

As of December 7th, Firefox is 10.3% of traffic there. This makes it the #2 browser, after Chrome (at 62.2%) -- a spot it has been dueling with Edge over for the last year or so.

I'm inclined to think that "people visiting wikipedia" is a fairly representative sample of "normal users", overall.