<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div apple-content-edited="true" class=""><br class="">
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<br class=""><div><blockquote type="cite" class=""><div class="">On Apr 23, 2015, at 1:07 PM, Brady Eidson <<a href="mailto:beidson@apple.com" class="">beidson@apple.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><blockquote type="cite" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><br class="Apple-interchange-newline">On Apr 21, 2015, at 3:39 PM, Chris Dumez <<a href="mailto:cdumez@apple.com" class="">cdumez@apple.com</a>> wrote:<br class=""><br class="">Hi,<br class=""><br class="">I would like to suggest we remove support for 'multipart/x-mixed-replace’ main resources while keeping support for multipart images.<br class=""><br class="">Based on Chrome usage data, this feature is extremely rarely used by Web sites (less than 0.00001% of page loads) [1]. This feature adds complexity to the loader and is a source of (security) bugs (e.g. [2] recently), current support also seems buggy.<br class=""><br class="">Current support in Safari / WebKit:<br class="">- Support is not great is WebKit. If you load a Motion JPEG main resource for example, it will keep creating a new ImageDocument and all its DOM tree for every frame (tested on Safari / Mac).<br class="">- It looks like support is broken on Safari on iOS (I tried a Motion JPEG main resource on iOS8, I see the first frame then a blank page that never finishes loading).<br class=""><br class="">Other browsers:<br class="">- Never supported by IE (including IE11) for any resource<br class="">- Chrome already dropped support for this (main resources only) almost 2 years ago [3].<br class="">- Firefox 37 still supports this based on local testing.<br class=""><br class="">Again, I am only proposing dropping support for main resources. For e.g., having an <IMG> element in a page whose src attribute points to a Motion JPEG would still work as intended.<br class=""></blockquote><br style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><span style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;" class="">I think it’s fine to drop support for multipart main resources besides MPJEG.</span><br style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><br style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><span style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;" class="">I think loading MJPEG as a main resource and having it be displayed as an ImageDocument is a valuable feature, and I object to dropping support for it. I’m not sure if that’s what you’re proposing, since it’s both a main resource and a multipart image.</span><br style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""></div></blockquote><div><br class=""></div></div>Yes, my proposal would break MJPEG as main resource. MJPEG is the main user of 'multipart/x-mixed-replace’ I believe. If we do want to keep supporting it, then we should probably fix support on both Mac (keeps recreating the ImageDocument) and iOS (Only shows the first frame).<div class=""><br class=""></div><div class="">Kr,</div><div class=""><div class="">--</div><div class=""><span style="font-size: 13px;" class=""> </span>Chris Dumez - Apple Inc. - Cupertino, CA</div></div></body></html>