HI sensor111, In order to troubleshoot what is happening, we might need a more clear picture of what is happening.

If it happens in more than one website, please grab two url examples that we can user for troubleshooting remotely.

If it only happens on one site, I might recommend contacting the site developer.

For a more savvy investigation there are the web developer tools that can point out errors in the web console if something is not showing up properly.

But before we go there, please consider updating your plugins and add ons to make sure there is nothing affecting the site there.

the 3d/2d sites you can also use https://aframe.io/docs/guide/

More advanced troubleshooting if you have a compatible gpu for webgl you can read up on these notes below: https://developer.mozilla.org/en-US/d.../WebGL_API

You can check the graphics section or the "Help > Troubleshooting Information" (about:support) page for error messages.

http://webglreport.com/?v=1 https://www.khronos.org/registry/webgl/sdk/tests/webgl-conformance-tests.html and https://developer.mozilla.org/en-US/docs/Web/API/WebGL_API/Tutorial/Creating_3D_objects_using_WebGL

In this tests Crome works OK but FF changed it's mind couple days ago.

Data from about:support page  : Graphics Adapter Description AMD M880G with ATI Mobility Radeon HD 4200 Adapter Drivers atiumd64 atidxx64 atiumdag atidxx32 atiumdva atiumd6a atitmm64 Adapter RAM 336 Asynchronous Pan/Zoom none Device ID 0x9712 Direct2D Enabled true DirectWrite Enabled true (6.2.9200.16571) Driver Date 8-4-2009 Driver Version 8.635.0.0 GPU #2 Active false GPU Accelerated Windows 7/7 Direct3D 11 (OMTC) Subsys ID 363f103c Supports Hardware H264 Decoding No; Hardware video decoding disabled or blacklisted Vendor ID 0x1002 windowLayerManagerRemote true AzureCanvasBackend direct2d 1.1 AzureContentBackend direct2d 1.1 AzureFallbackCanvasBackend cairo AzureSkiaAccelerated 0 (#0) Error [D2D1.1] 4CreateBitmap failure Size(32,8200) Code: 0x80070057 format 0 (#17) Error GLContext is disabled due to a previous crash. (#18) Error GLContext is disabled due to a previous crash. (#19) Error GLContext is disabled due to a previous crash. (#20) Error GLContext is disabled due to a previous crash. (#21)

Did Firefox create any specific pref to disable WebGL?

Try to rename (or delete) the prefs.js file to reset all prefs to the default value.

• http://kb.mozillazine.org/Preferences_not_saved
• http://kb.mozillazine.org/Resetting_preferences

You can use this button to go to the current Firefox profile folder:

• Help > Troubleshooting Information > Profile Directory: Show Folder (Linux: Open Directory; Mac: Show in Finder)
• http://kb.mozillazine.org/Profile_folder_-_Firefox

Windows hides some file extensions by default. Among them .html and .ini and .js and .txt and you may only see a file name without file extension. You can check the file extension (type) in the properties of the file in Windows Explorer via the right-click context menu.

Yep - thats helps.

Can I somehow take my saved preference back without engendering webgl ?

I had outdated drivers, and Mozilla might have blacklisted my drivers. I updated the drivers and with no success. I still can't use webgl. I even went into about:config and enabled all of the appropriate configs to attempt a workaround. No luck. I have not yet added my card to the whitelist. I have a 650GTX with the latest drivers. It should work.

After a crash loading a page with WebGL (from the O'Reilly book about WebGL), I had the same problem on a Linx Mint 17.3 Cinnamon 64 bit, FF version 45. The page that caused the crash was this one (in fact the entire laptop crashed, not just FF): https://github.com/tparisi/WebGLBook/blob/master/Chapter%203/graphics-earth-moon.html

The following worked for me:

Close firefox and edit the file: /home/[username]/.mozilla/firefox/mwad0hks.default/prefs.js

Find the lines that contain "glcontext" and delete those lines. Start firefox. WebGL works again.

It would be great if there'd be a way to do this in the UI - non-tech-savvy users have no chance at fixing this ..

jonas-e, make the preference change in about:config and not the prefs.js file which is what changes made in about:config writes to.

Thanks. At first I couldn't find anything there, inspired by your comment I now see that there are four entries in about:config:

gfx.crash-guard.glcontext.appVersion;45.0 gfx.crash-guard.glcontext.deviceID;Mesa DRI Intel(R) Haswell Mobile gfx.crash-guard.glcontext.driverVersion;3.0 Mesa 10.5.9 gfx.crash-guard.status.glcontext;2

I wonder which one makes the difference - could it be the last one - status.glcontext? Is webgl disabled if the value is 0?