ccsm default config cause screen tearing

[Xiang WU]

Bug discreption and reproduce:
Play video using smplayer or firefox flash plugin in fullscreen mode.
When the video make large horizon moves, screen tearing appears.
Try to change ccsm(CompizConfig Settings Manager) config.
Open ccsm, goto Composite, check off "Unredirect Fullscreen Windows".
Play video again, everything ok.
Check on, screen tearing again.

Check on "Unredirect Fullscreen Windows",
Change "Unredirect Match" from:
(any) & !(class=Totem) & !(class=MPlayer) & !(class=Vlc) & !(class=Plugin-container) & !(class=Firefox)
to:
(any) & !(class=totem) & !(class=mplayer) & !(class=vlc) & !(class=plugin-container) & !(class=firefox)
which is just change all upper letters into lower letters,
play video again, everything ok.

So I guess this problem is caused by inproper default configuration of "Unredirect Match".
The default config includes upper cases like "MPlayer", which should be "smplayer". This
cause a mismatch of window class or something.

System info:
Intel Core i7-4700MQ CPU @ 2.40GHz
Nvidia GT755M with nouveau driver from xserver-xorg-video-nouveau
(I'm not sure it's using nvidia card or i7)
Ubuntu 14.04 LTS
CompizConfig Settings Manager 0.9.11.2
Compiz 0.9.11.2
unity 7.2.2

[JaSauders (jasauders)]

I stumbled across this almost on accident on my 14.04 rig, which acts as a home theatre PC in the living room. Netflix proved to be quite choppy with lots of tearing in Chrome. I tried a multitude of settings before coming to find the very setting Xiang spoke about above ended up being the fix.

Likewise, I just spun up a fresh install of 15.04. Right away, YouTube video tearing. Like before, I fired up compizconfig-settings-manager and switched Composite >> Unredirect Fullscreen Windows to be unchecked.

Just like that, tearing is gone.

In all reality, this should default to uncheck. It would alleviate a multitude of headaches that users have with screen tearing. After all, not everybody knows that compizconfig-settings-manager exists, or that they should install it post-Ubuntu-install just to flip a checkbox to rectify this issue.

[Colin S. (cbs228)]

After I installed a radeon graphics card with the open source drivers, I began experiencing severe tearing in VLC on Ubuntu 15.10. The CCSM workaround in the bug report works for me. "Unredirect Fullscreen Windows" is on by default in 15.10. "Unredirect Match" needed updating, however. I changed the "Vlc" entry to "vlc" (all lowercase), and my tearing problems went away.

If the setting description is any indication, then Composite is searching through the X11 window class (WM_CLASS) for the "Unredirect Match" setting. `xprop` reports VLC's full-screen window to have a class of "vlc" (all lowercase). Perhaps VLC changed their window class at some point?