Earlier quoted context omitted.
I just wish they'd moved to Gecko instead of Chromium. It's not like Gecko is an inherently inferior engine by any stretch, and it would significantly bolster their marketshare so that developers actually have to test against it.
One huge advantage the Chromium has over Gecko is Google's Security Team (ie Project Zero). For most users, the web browser is one of the biggest attack surfaces and having arguably the best security team behind the browser engine is a good thing.
Yes some of that might be thanks to PZ, but that’s beside the point, isn’t it?
Choosing Mozilla’s platform would have been better for code diversity, which has its own distinct security benefits.