All this looks like to me is Google developers use Chrome (surprise!). I've seen plenty of issues exactly like this at web shops where developers primarily use Chrome.
You missed the part how it was about the conflict of interest. "We're on the same side" wasn't really true.
Especially at the higher level, Mozilla was complicit in accepting money from a competitor.
Make no mistake, that absolutely distorted how they ran the company over the next decade. That's why Firefox is so "meh" right now, why Servo got killed, why Mozilla is being seriously mismanaged.
I just can't understand why Chrome can't handle a hundred open tabs if the developers use it primarily. Firefox handles it with about the same RAM usage as six hundred open tabs.