User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:29.0) Gecko/20100101 Firefox/29.0 Build ID: 20150404130542 Steps to reproduce: 1) Disable Flash. This will trigger the HTML5 player. (I also have disabled Cisco H264, so it uses WebM. DRM support is disabled too) 2) Go to YouTube, open a video and play it :) 3) If Auto Play is off, put it on Actual results: The memory increases by each video viewed to enormous sizes. 2 gigabyte of RAM usage after a few hours is not unusual with Auto Play. According to PulseAudio, the audio streams are kept open instead of being closed after a video has been viewed. Expected results: Firefox should close GStreamer connections after a video has been played. This has been an issue for many Firefox releases for me. This can also be something else than GStreamer, but it's the only thing I think of myself.
My custom user agent was on while posting this issue. It should have been Mozilla/5.0 (X11; Linux x86_64; rv:37.0) Gecko/20100101 Firefox/37.0
Weird, now it works like it should..
Should the issue resurface, please test in a brand new profile. https://support.mozilla.org/kb/profile-manager-create-and-remove-firefox-profiles If the problem persists, attach memory leak information as detailed at https://developer.mozilla.org/docs/Mozilla/QA/Bug_writing_guidelines#For_specific_types_of_bugs (In reply to Geoffrey Db from comment #0) > 1) Disable Flash. This will trigger the HTML5 player. (I also have disabled > Cisco H264, so it uses WebM. The OpenH264 plug-in is only used for WebRTC, so it has nothing to do with HTML5 video playback. Right-click the video and choose Stats for Nerds. Check the Mime Type row for the video format.