Lifehacker – Top 10 Firefox 3.5 Features – Firefox 3.5 – My two favorite features are as follows …
Keyword AwesomeBar filters – Firefox 3's AwesomeBar/address bar offers a speedy list of suggestions to complete whatever you're typing. That's great, but that list comes from your page history, bookmarks, and tags, and can be matched by URL or name, leaving some results almost uselessly cluttered. This gets fixed with special character filters in the next Firefox. Restrict a search by typing "life *" for just your bookmarks with the words "life" in them, or just your tagged "lh" items with "lh +". Anything that really makes getting back to importantly web destinations quickly is a welcome upgrade.
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Video superpowers with HTML 5 – If you're viewing a page coded in HTML 5 with video in an open-source format like Ogg Vorbis or Theora, Firefox 3.5 treats that video like it's just part of the page, not a separate little island of Flash content. That means instant commenting on videos. It could also mean offering links from inside a tutorial video that offer more details on what's being shown—soldering tips on an iPhone repair guide would be keen. In general, it's just a promising step forward into a seamless melding of video and text on a future web.