User Agent: Mozilla/5.0 (Windows NT 6.1; rv:8.0.1) Gecko/20100101 Firefox/8.0.1 Build ID: 20111207031110 Steps to reproduce: 1. install add-on Firegesture (FG for short below), it's a AMO feature add-on with roughly 550k users. link: https://addons.mozilla.org/en-US/firefox/addon/firegestures/?src=search 2. By default, FG will draw right-click mouse down trail, and some site will make right-click response really slow, e.g. GitHub source page, similar to Bug 704911. 3. If turning off "Drawing Trail" option, this issue disappears.
This addon modifies the DOM on right click, looks like. There are all sorts of ways that could go wrong performance-wise depending on the DOM and the modifications they make to it... Probably worth retesting once bug 705877 is fixed.
Bug 705877 landed on inbound. Could you maybe retest with nightlies a few days from now?
(In reply to Boris Zbarsky (:bz) from comment #2) > Bug 705877 landed on inbound. Could you maybe retest with nightlies a few > days from now? test with today(20120313) nightly, issue fixed
Great, thank you for testing that!