On 26 April 2018 at 12:23, Konstantin Tokarev <annu...@yandex.ru> wrote: > 26.04.2018, 19:16, "Michael Catanzaro" <mcatanz...@igalia.com>: >> On Thu, Apr 26, 2018 at 11:13 AM, Michael Catanzaro <mcatanz...@igalia.com> >> wrote: >>> By fixing the WebKit bug, of course. And in the meantime you can work >>> around it on the server side by not using <img src=mp4>, right?
Today, we can work around it by ignoring the Accept field. However, tomorrow once the bug is fixed we will be in the paradox of not knowing which versions of Safari are telling the truth. >> Consider the other perspective on this problem. If other servers look >> at the WebKit version in the UA to determine if WebKit supports img >> src=mp4, other WebKit ports that don't support this are going to be out >> of luck and get broken pages. I know that's not what you're doing -- >> you're looking at iOS version instead, and only doing it to work around >> a specific bug, which is much better -- but the problem of websites >> sending bad content based on bad user agent parsing is so severe that >> we don't have many good options, here. :/ > > Not to mention those evil people who reject page loading for user agents > they don't (want to) support How does locking the UA solve the misbehaving parsers in the wild? They will still misbehave and break the user experience. However, those of us that are trying to optimize the user experience by working around bugs for specific versions are now handicapped and punished. The reality is that bugs exist. There is a give and take here where the content negotiation is sometimes smarter on the client, and sometimes smarter on the server. In the case of media, the server is usually smarter and must be because of the long tail of adoption. Ideally everyone on the planet will adopt to ios V.Latest overnight, but sadly this will not be the case. Servers must account for the long tail of users on many different versions. Right now we are forced to decide to apply a solution that works only for v.latest, or apply a solution that works for v.lowest-common-denominator. In both scenarios we compromise the user experience. Ideally we wouldn't have to sacrifice some users and would be able to account for bugs in the wild. As I said before, if this detail is available in javascript, then why hide it on the wire? Perhaps it's time for a User-Agent2 with precise feature declarations? Even still a version number is needed because, well, bugs. While I understand the fingerprinting concern, I'm not particularly convinced that UA obfuscation is the best solution for users and the user experience. Without opening up the religious debate of fingerprinting with the UA, how can provide enough detail (version numbers) so that service providers can work toward the greater good of improving the user experience? Is there room for compromise? /colin _______________________________________________ webkit-dev mailing list webkit-dev@lists.webkit.org https://lists.webkit.org/mailman/listinfo/webkit-dev
