I'm running into this issue right now with the locked UA. Here are the challenges: 1. ios 11.3 safari bug broke <img src=mp4> despite advertising `accept: video/*` in the request. (see bug 185029). I now need to use UA detection to patch versions of a response based on existing bugs. In short, we as an industry, depend on UA parsing to work around bugs. This happened last year when the jp2k support increased to 10bit depth and the decoder was inflating the 8bit colour pallet to 10bit. We needed to use UA parsing to determine if it was safe to send jp2k images to a device. I have a laundry list of other examples where the server might actually know more than the client to prevent a) a broken user experience and b) prevent cellular data waste.
2. Javascript based feature detection is inefficient and slows down safari' preloader. The preloader is one of the best performance enhancements to come to the modern browser. Using javscript for feature detection is a step backward for the preloader. Webkit does not provide enough declarations of its feature set in HTTP headers so we resort to UA device characteristics. If the features are available with javascript inquiry, then how is that any different than exposing these features at request time? In short, we are stuck. blocking the UA like this will degrading the user experience because it will force us to either not take advantage of cell-data/cpu/battery improvements (like sending mp4s instead of animated gifs) or it will force us to use javascript and likewise degrade the user experience with slower web experiences. How do we navigate this? /colin On 26 April 2018 at 11:22, Michael Catanzaro <mcatanz...@igalia.com> wrote: > On Thu, Apr 26, 2018 at 7:15 AM, Ricky Young <ri...@gmx.com> wrote: >> >> I guess that soon it won't be possible to determine iOS version >> distribution using User-Agent sniffing. Right? Is there an alternative for >> the browser to tell the iOS version? > > > Hi, > > The very point of no longer sending the verison in the user agent is to make > it difficult for websites to determine the operating system version. > > We already have to deal with enough serious web compatibility problems > caused by the rest of the information in the user agent. I'm pleased that > the version number is now stable -- that's a huge improvement -- but I won't > be happy until Safari and other major browsers start sending > fully-randomized UAs, or else a stub or blank UA ("Mozilla/5.0"). > > Michael > > > _______________________________________________ > webkit-dev mailing list > webkit-dev@lists.webkit.org > https://lists.webkit.org/mailman/listinfo/webkit-dev _______________________________________________ webkit-dev mailing list webkit-dev@lists.webkit.org https://lists.webkit.org/mailman/listinfo/webkit-dev