It's the choice of either blocking some extension(s) or getting their whole domains blocked in russia, so mozilla chose the first

I am not going to support the foundation.

In 2021, Mozilla Corporation generated $441 million in royalties, which represented almost 89% of its income.

Source

As of 2021, Mozilla (including the Foundation and the wholly owned For-Profit Corporations), had total assets worth over $1.1 Billion USD [...]

Source (inb4 "bUt LunDukE iS bAd" - his personal and political views have nothing to do with his research analysis work in this article)