Firefox incorrectly blacklists system for WebGL

[Jeremy Nation]

This is with Ubuntu 16.04.

Using the Ubuntu-provided Firefox 57.0, if I go to https://get.webgl.org/ I get the message:

"Hmm. While your browser seems to support WebGL, it is disabled or unavailable. If possible, please ensure that you are running the latest drivers for your video card."

In the JavaScript developer console there are some messages, including:

"Error: WebGL warning: Failed to create WebGL context: WebGL creation failed:
* Refused to create native OpenGL context because of blacklist entry: FEATURE_FAILURE_OPENGL_1
* Exhausted GL driver options."

There are similar messages for WebGL in about:support.

However if I download Firefox 57.0 from https://ftp.mozilla.org/pub/firefox/releases/57.0/linux-x86_64/en-US/firefox-57.0.tar.bz2 and use that to go to https://get.webgl.org/ , I get the message "Your browser supports WebGL".

So it looks like Ubuntu-provided Firefox has a problem while Mozilla-provided Firefox doesn't. (FYI, I reported a similar problem in https://bugs.launchpad.net/ubuntu/+source/firefox/+bug/1724705 , where DRM-protected content doesn't work with Ubuntu-provided Firefox but does work with Mozilla-provided Firefox.)

[Jeremy Nation (jnation)]

Using the Ubuntu-provided Firefox 58.0, I now see a spinning cube and the text "Your browser supports WebGL" at https://get.webgl.org/ so this seems to be fixed.

[Thomas Mayer (thomas303)]

I still get this message, using FF 62.0, ubuntu 18.04.

[Jeremy Nation (jnation)]

I'm confirming that this still works for me, as I described in my previous comment, using Firefox 62.0 and Ubuntu 18.04.

[Olivier Tilloy (osomon)]

Thomas, can you share details of your graphics card and driver in use?

[Stefano (stevexyz)]

Same here, WebGL not activated. I'm trying to run scratch.mit.edu programs.

No graphic card on this MSI U100 netbook, but there are the MESA packages installed (libglx-mesa0, libgl1-mesa-dri,...)

error example in about config:
gfx.blacklist.webgl2.failureid;FEATURE_FAILURE_OPENGL_1