> Also, even since 57, this week Firefox ("stable" build) consistently gets hung up with just one tab open and spins 100% CPU on one thread. I mean, this proba

> Also, even since 57, this week Firefox ("stable" build) consistently gets hung up with just one tab open and spins 100% CPU on one thread. I mean, this probably isn't the right venue to ask about this, but that sounds rather serious. I know you're probably a bit disenfranchised at this point, but could I ask you to capture a profile using https://perf-html.io https://perf-html.io and file a bug? If filing a bug is too much work, you can email me (email in profile), but filing a bug will get more eyes on it quicker.