We don't have Wayland setup to test and confirm this issue as of now. 

Tentatively adding Internals>Media and Blink>Fullscreen components and cc'ing reveman@ (https://cs.chromium.org/chromium/src/ash/wayland/OWNERS?q=wayland&sq=package:chromium&dr) for further help in triaging this issue.

Thanks!

As per comment#2 we don't have Wayland setup to test and confirm this issue as of now, Hence adding label TE-NeedsTriageHelp and requesting someone from "Internals>Media" team to have a look into this and help in further triaging it.

Thanks!

dale@, do you know who has Wayland setup? I don't have the environment either.

Chrome doesn't have Wayland output support today so I assume this is X11 Chrome on a Wayland desktop through Xwayland.

dalecurtis@, how do we prevent monitor from going to sleep on a standard x11 Linux desktop? Same APIs should work with a Xwayland setup unless the desktop environment is failing to handle that properly.

The platform just needs to implement a WakeLock:

https://cs.chromium.org/chromium/src/content/browser/media/media_web_contents_observer.cc?type=cs&sq=package:chromium&l=315
https://cs.chromium.org/chromium/src/services/device/wake_lock/
https://cs.chromium.org/chromium/src/services/device/wake_lock/power_save_blocker/

https://cs.chromium.org/chromium/src/base/nix/xdg_util.cc?l=56 is probably not returning what we need on this desktop. Given the type environment we detect and the wake lock that is supported we should be able to correct this.

reveman@, please re-assign appropriately if need.

Need feedback from reporter for what type of desktop environment this is.

The desktop environment is Gnome Shell on Wayland from the default installation of the latest Fedora.

Digging further I can confirm that the Chrome is using XWayland.

What is XDG_CURRENT_DESKTOP set to? What does "echo ${XDG_CURRENT_DESKTOP}" in a terminal return?

$ echo $XDG_CURRENT_DESKTOP
GNOME
$

hm, we should be using the org.gnome.SessionManager service in that case and I'm not sure why that is not working. Is org.gnome.SessionManager dbus service not running on your system?

$ python
Python 2.7.14 (default, Mar 14 2018, 13:36:31) 
[GCC 7.3.1 20180303 (Red Hat 7.3.1-5)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import dbus
>>> bus = dbus.SessionBus()
>>> bus.get_object('org.gnome.SessionManager','/org/gnome/SessionManager')
<ProxyObject wrapping <dbus._dbus.SessionBus (session) at 0x7fa574f2fcb0> :1.12 /org/gnome/SessionManager at 0x7fa569e83110>
>>> 

$ ps auxfww | grep dbus | grep -v grep
dbus       879  0.0  0.0  47300  5764 ?        Ss   20:13   0:02 /usr/bin/dbus-daemon --system --address=systemd: --nofork --nopidfile --systemd-activation --syslog-only
gdm       1015  0.0  0.0  45876  4460 ?        Ss   20:13   0:00  \_ /usr/bin/dbus-daemon --session --address=systemd: --nofork --nopidfile --systemd-activation --syslog-only
gdm       1066  0.0  0.0  45532  4172 ?        S    20:13   0:00  |   \_ /bin/dbus-daemon --config-file=/usr/share/defaults/at-spi2/accessibility.conf --nofork --print-address 3
mgaydar+  1485  0.0  0.0  46564  5148 ?        Ss   20:13   0:00  \_ /usr/bin/dbus-daemon --session --address=systemd: --nofork --nopidfile --systemd-activation --syslog-only
mgaydar+  1575  0.0  0.0  45536  4080 ?        S    20:13   0:00  |   \_ /bin/dbus-daemon --config-file=/usr/share/defaults/at-spi2/accessibility.conf --nofork --print-address 3

It seems to be working. VLC player manages to keep the display from sleeping (I don't know how). Hangouts calls are unable to prevent the display from sleeping. So it seems like browser issue.