You don't really have to; the AO3 lets you set up your preferred browser page title format, so it's changeable on that end of things. It's a little limited - I can't get my preferred [Fandom] Title, by Author with the nice clean square brackets to match 15 years of delicious/pinboard bookmarking, but I can get -Fandom- Title, by Author, which is close enough.

And if I'm using the button on a works list, I can always just tweak by hand. :)