177483 2017-09-26 03:51:23 -0700 Appending media to the start of a buffer range drops buffer after the append. 2019-09-20 15:35:17 -0700 1 1 1 Unclassified WebKit Media Safari 10 Mac macOS 10.12 RESOLVED CONFIGURATION CHANGED InRadar P2 Normal --- 1 robert.bryer webkit-unassigned eric.carlson jeremyj-wk jer.noble jesus jonlee peng.liu6 webkit-bug-importer oldest_to_newest 1352629 0 robert.bryer 2017-09-26 03:51:23 -0700 When appending media to the start of a buffered range, webkit will remove a portion of buffer after the append, keeping the buffer as two separate ranges. To reproduce: http://reference.dashif.org/dash.js/v2.6.0/samples/dash-if-reference-player/index.html 1. Click load. 2. Seek forward to a time like 3:00, await some buffer at this time. 3. Seek back to 2:45, play until 3:00. 4. Observe that there is a gap in the buffer at the first segment downloaded(between 176 and 178). When appending the segment again to fill the gap, a new gap appears at the next segment boundary, and so on - effectively meaning we need to replace all the buffered media from 3:00 onwards. The fact that the above example doesn't play out is our fault(we should be checking .buffered when deciding what to fetch, and we have a fix already for this so we can make it play). But we probably shouldn't need to replace all the buffer ahead after seeking backwards. What's going on here? 1561646 1 webkit-bug-importer 2019-08-15 11:24:29 -0700 <rdar://problem/54354873> 1571396 2 peng.liu6 2019-09-16 19:59:14 -0700 Hi Robert, is this bug still reproducible? Thanks! 1572710 3 robert.bryer 2019-09-20 02:50:41 -0700 On Safari 12.1.2 I can't reproduce it, it looks fixed - It was reported for a Safari 10 version though. 1572927 4 peng.liu6 2019-09-20 15:35:17 -0700 Great! Thanks for the information.