Pale Moon's JavaScript support was atrocious last time I checked, indicating that it's not actually keeping pace with Mozilla. I was developing a user script at

Pale Moon's JavaScript support was atrocious last time I checked, indicating that it's not actually keeping pace with Mozilla. I was developing a user script at the time and had to ask a user to stop using what amounts to a copy of Firefox that's several years past it's expiry. Who knows what kind of issues are lingering around? Given that Pale Moon users advertise themselves as power users they might make quite a valuable target.