On 2017-02-16 6:06 PM, Xidorn Quan wrote: > On Fri, Feb 17, 2017, at 01:38 AM, Ehsan Akhgari wrote: >> On 2017-02-16 1:51 AM, Xidorn Quan wrote: >>> Tracking bug: https://bugzilla.mozilla.org/show_bug.cgi?id=903372 >>> >>> Summary: >>> * It has been removed from the spec years ago. >>> * No other browser supports it. >>> * We pay performance penalty for it. >>> * It makes things trickier for stylo to handle URL values. >>> >>> The tricky thing is that nsParserUtils::ParseFragment currently relies >>> on xml:base. That is going to be fixed in >>> https://bugzilla.mozilla.org/show_bug.cgi?id=1313278 >>> >>> Are there any objections? >> >> Do we have telemetry on its current usage? We've tried to remove Gecko >> only features with the justification that since no other browser >> supports it nobody probably uses it, and we have been proven wrong. It >> seems like we need to have some information that shows this isn't used >> in the wild before discussing whether we should remove it. > > I don't think we have telemetry on that... We can probably add one, but > I'm not sure where is the best hook point of it. Is there telemetry for > any other attribute I can take as a reference?
There are lots of telemetry probes, not quite sure what kind of example you are looking for. Can you please be more specific? In terms of what you want to measure, you should measure the places where xml:base is currently used. I know of <http://searchfox.org/mozilla-central/rev/ea31c4b64f34a29415a69fb768f8051495547315/dom/base/FragmentOrElement.cpp#383> and <http://searchfox.org/mozilla-central/rev/ea31c4b64f34a29415a69fb768f8051495547315/toolkit/components/feeds/FeedProcessor.js#1359>, not 100% sure if that covers it all. Usually the first step in measuring the usage is to define what you actually want to measure. One immediate idea that comes to my mind is what percentage of documents that we load use <xml:base> to define the base URI. But there are many other ways to formulate the usage, so some thought on that is necessary. _______________________________________________ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
