Shared components used by Firefox and other Mozilla software, including handling of Web content; Gecko, HTML, CSS, layout, DOM, scripts, images, networking, etc. Issues with web page layout probably go here, while Firefox user interface issues belong in the Firefox product. (More info)
Created attachment 567660[details][diff][review]
I doubt this will get us any wins, but I don't think we need to try to invalidate all layer contents on all children when we switch cards in a deck.