844244 - when webgl is disabled, getContext("experimental-webgl") throws NS_ERROR_FAILURE instead of returning null

Status: RESOLVED DUPLICATE of bug 645792

(Core :: Graphics: CanvasWebGL, defect)

Description

[bugzilla]

User Agent: Mozilla/5.0 (Windows NT 5.1; rv:19.0) Gecko/20100101 Firefox/19.0
Build ID: 20130215130331

Steps to reproduce:

1. go to about:config
2. set "webgl.disabled" to "true"
3. in the console, enter: document.createElement("canvas").getContext("experimental-webgl")


Actual results:

This throws:

Error: Component returned failure code: 0x80004005 (NS_ERROR_FAILURE) [nsIDOMHTMLCanvasElement.getContext]


Expected results:

If an unsupported value is passed to `getContext`, it must return `null`. If WebGL is supported by the user agent, but not with the currently used configuration, calling `getContext` with the WebGL contextId must return `null`, too.

http://www.whatwg.org/specs/web-apps/current-work/multipage/the-canvas-element.html#dom-canvas-getcontext

Comment 1

[Everton da Silva Marques]

Similar issue:

https://bugzilla.mozilla.org/show_bug.cgi?id=645792