Maksim, to answer your question, the point is not to retrieve on hover but as soon as an anchor's href is parsed, so it is wasteful, but the Chromium guys say they observe it doesn't put a significant pressure on DNSes as the average page as few external links. My approach would be to cap the number of resolution to something (configurable) like 40 per page, getting most of the benefit on news site, without the DDOSing behaviour. It does give a kind of "what could possibly go wrong" feeling though :-)
DOM namespace changes --- vtokarev --- done (in trunk)
Class attribute hashconsing for improved css selectors performance --- vtokarev
Implementation that we have currently is significantly slower on specific test case (probably less on real-life pages). Anyway, it should improve performance (maybe even memory usage), with small drawback on complexity
Might not be a good name, but I mean: bug #170185, part of bug #165601, part of bug #162498, later bts and dupes of bug #145666, and likely some others. My initial description is probably wrong, though --- the problem is the hack in handling window.document that creates the document by calling begin/write/end is doing so on a document with a parser active; one of the triggers is probably because the restoration of frames from KHTMLPageCache may happen in the wrong order, but the various reports suggest it's not the only case. (The reason for the original description is that I recalled seeing quite a few reports mentioning the same m_scriptExecuting assert, e.g. bug #118104 for a long time, and figured it's time to get rid of this; some of those are actually mixed in with the dupes of the above). -S.E.