I had a problem redrawing the Chromium page, and I noticed on the timeline that the Recalculate Style shot at what I think is very high:

Please note that this event is fired at this speed (5000 or so in 30 seconds) all the time when the page is open - inactive or not. I am wondering if this is normal, but my question is:
What triggers / fires events for which the stack does not appear in the chronological timeline?
This question is related, but not quite the answer I'm looking for, because I know what “Recount Style” means, I just don't know what causes it.
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