They include extensive Telemetry as well, fired most of their employees while significantly increasing the executive pay once which lead to the death of various projects most notably Servo, they perform experiments on their users without notice, the build in tracking blocker is anything but great and they repeatedly defended Google for very shitty moves (probably because that's who pays them), they spread rumors about Google ending payment once to cash out and they keep inventing products in the hope of even more money most of which goes to talentless executives rather than development.

This list is out of my head and might not be 100% accurate and complete but what I can promise you is that Mozilla sucks too! :/