Refine according to comments on v1.0.0
Refine according to comments on v1.0.0

"DOM mutation events profoundly degrade performance, and that degradation is not reversed by removing the listeners. We can't allow mutation listeners except when they're absolutely necessary, and never for the top-level browser document. Please see https://developer.mozilla.org/en/XUL_School/Appendix_F:_Monitoring_DOM_changes for more information." (Reviewed by Leszek Życzkowski)

aidistan/firefox-weixin-danmu