Bug#873546: firefox-esr: fails to play some YouTube videos (which play correctly on chromium)

[Francesco Poli (wintermute)]

Package: firefox-esr
Version: 52.3.0esr-2
Severity: normal

Hello and thanks for maintaining Firefox in Debian!

I noticed that some YouTube videos[^NOTE] fail to be played on firefox-esr,
but are played with no issues on chromium (hence the videos themselves
do not seem to be somehow 'broken'...).

[^NOTE]: such as <https://www.youtube.com/watch?v=rm6uCcHQM9w>

The playback never starts and stays in an eternal buffering state. Shortly,
the message

  If playback doesn't begin shortly, try restarting
                  your device.

appears.  Nothing else happens.

I have already tried in safe mode:

  $ firefox-esr -safe-mode

but nothing changed.

A good number of Youtube videos are played flawlessly, but some fail,
as described above.


I have already taken a look at other YouTube-related bug reports,
but my problem seems to be a distint one...

What could I do in order to debug this issue?
Please let me know.

Thanks for your time!



-- Package-specific info:

-- Extensions information
Name: Application Update Service Helper
Location: ${PROFILE_EXTENSIONS}/aushelper at mozilla.org.xpi
Status: enabled

Name: Cookie Monster
Location: /usr/share/xul-ext/cookie-monster
Package: xul-ext-cookie-monster
Status: enabled

Name: Debian buttons
Location: /usr/share/xul-ext/debianbuttons
Package: xul-ext-debianbuttons
Status: enabled

Name: Default theme
Location: /usr/lib/firefox-esr/browser/extensions/{972ce4c6-7e08-4474-a285-3208198ce6fd}.xpi
Package: firefox-esr
Status: enabled

Name: HTTPS Everywhere
Location: /usr/share/xul-ext/https-everywhere
Package: xul-ext-https-everywhere
Status: enabled

Name: Multi-process staged rollout
Location: ${PROFILE_EXTENSIONS}/e10srollout at mozilla.org.xpi
Status: enabled

Name: NoScript
Location: /usr/share/xul-ext/noscript
Package: xul-ext-noscript
Status: enabled

Name: Pocket
Location: ${PROFILE_EXTENSIONS}/firefox at getpocket.com.xpi
Status: enabled

Name: Uppity
Location: /usr/share/xul-ext/uppity
Package: xul-ext-uppity
Status: enabled

Name: User Agent Switcher
Location: /usr/share/xul-ext/useragentswitcher
Package: xul-ext-useragentswitcher
Status: enabled

Name: Web Compat
Location: ${PROFILE_EXTENSIONS}/webcompat at mozilla.org.xpi
Status: enabled

-- Plugins information
Name: Shockwave Flash
Location: /usr/lib/gnash/libgnashplugin.so
Package: browser-plugin-gnash
Status: enabled


-- Addons package information
ii  browser-plugin 0.8.11~git20 amd64        GNU Shockwave Flash (SWF) player 
ii  firefox-esr    52.3.0esr-2  amd64        Mozilla Firefox web browser - Ext
ii  xul-ext-cookie 1.3.0.5-1    all          manage cookies in a whitelist-bas
ii  xul-ext-debian 1.11-3       all          Buttons for querying Debian-relat
ii  xul-ext-https- 5.2.8-1      all          extension to force the use of HTT
ii  xul-ext-noscri 5.0.9-1      all          permissions manager for Firefox
ii  xul-ext-uppity 1.5.8-5      all          toolbar button to "go up" on the 
ii  xul-ext-userag 0.7.3-3      all          Firefox addon that allows the use

-- System Information:
Debian Release: buster/sid
  APT prefers testing
  APT policy: (800, 'testing'), (500, 'unstable')
Architecture: amd64 (x86_64)

Kernel: Linux 4.12.0-1-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8), LANGUAGE=en_US:en (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages firefox-esr depends on:
ii  debianutils               4.8.2
ii  fontconfig                2.12.3-0.2
ii  libasound2                1.1.3-5
ii  libatk1.0-0               2.24.0-1
ii  libc6                     2.24-14
ii  libcairo-gobject2         1.14.10-1
ii  libcairo2                 1.14.10-1
ii  libdbus-1-3               1.11.16+really1.10.22-1
ii  libdbus-glib-1-2          0.108-2
ii  libevent-2.1-6            2.1.8-stable-4
ii  libffi6                   3.2.1-6
ii  libfontconfig1            2.12.3-0.2
ii  libfreetype6              2.8-0.2
ii  libgcc1                   1:7.2.0-1
ii  libgdk-pixbuf2.0-0        2.36.5-2
ii  libglib2.0-0              2.53.4-3
ii  libgtk-3-0                3.22.18-1
ii  libgtk2.0-0               2.24.31-2
ii  libhunspell-1.6-0         1.6.1-2
ii  libjsoncpp1               1.7.4-3
ii  libnspr4                  2:4.16-1
ii  libnss3                   2:3.31-1
ii  libpango-1.0-0            1.40.6-1
ii  libsqlite3-0              3.19.3-3
ii  libstartup-notification0  0.12-4+b2
ii  libstdc++6                7.2.0-1
ii  libvpx4                   1.6.1-3
ii  libx11-6                  2:1.6.4-3
ii  libx11-xcb1               2:1.6.4-3
ii  libxcb-shm0               1.12-1
ii  libxcb1                   1.12-1
ii  libxcomposite1            1:0.4.4-2
ii  libxdamage1               1:1.1.4-3
ii  libxext6                  2:1.3.3-1+b2
ii  libxfixes3                1:5.0.3-1
ii  libxrender1               1:0.9.10-1
ii  libxt6                    1:1.1.5-1
ii  procps                    2:3.3.12-3
ii  zlib1g                    1:1.2.8.dfsg-5

firefox-esr recommends no packages.

Versions of packages firefox-esr suggests:
ii  fonts-lmodern          2.004.5-3
ii  fonts-stix [otf-stix]  1.1.1-4
ii  libcanberra0           0.30-3
ii  libgssapi-krb5-2       1.15.1-2
pn  mozplugger             <none>

-- no debconf information