unusual amount of firefox updates? lately

Yes they are frequent. Every two weeks.

Mozilla will release Firefox updates every two weeks starting September – the change doubles the update frequency from monthly to biweekly, with Firefox 155 launching September 1st. The time between discovering a security flaw and hackers exploiting it is getting shorter, forcing faster patch releases. Mozilla says features won't be rushed and the two-week cycle will be monitored to see if adjustments are needed. https://cybernews.com/security/mozilla-update-cycle-firefox/

How do you know about them, have you set to auto-update or do you choose when to do so?

Hello

A article https://www.camp-firefox.de/artikel/1231-firefox-features-updates-künftig-alle-zwei-wochen

This other discussion https://support.mozilla.org/en-US/questions/1590804

I don't know if the F/F updates are legit; I used to get updates, once in while.Lately seems updates are every few days or everyday.Not sure if these are spam or getting hacked?

Why the duplicate thread when you posted this question the day before and got two replies. https://support.mozilla.org/en-US/questions/1603169

There has been only one update since the Firefox 155.0 Release which was Fx 155.0.1 released on Sept 4th.

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