I think forking is the way to go.
That way, you can collect the people who like Chrome's current and soon to be former aesthetic and get them using Pale Moon with the old Chrome theme if they don't like the the actual Chrome's new look, *but* still also have a theme so that future Chrome users who like it's soon-to-be-current look but want Pale Moon's increased customizablity, extendability, and privacy to get all that in one package (Pale Moon plus the new theme). Essentially, you get the people soon to be disenfranchised by Chrome's changes *and* the people who in the future might want a smooth transition to Pale Moon from the Chrome of the future, which to them will be the Chrome of the present.
To be fair, though, I should note that:
a) I don't like Chrome's look (past, present, or future- at least not the future that is being previewed, I can't say passed that because I don't have a crystal ball
) and thus am not using and don't plan to use a Chrome-like theme. So my vote may not count, which is fine with me.
b) It's easy for me to say fork it because I don't have to code or maintain the fork. I understand why someone might not want to do twice the work
c) If I was going to be completely selfish, I'd say do neither and work on a Pale Moon compatible fork of Privacy Badger instead.
