Re: Watching HTML5 video on GNU Guix?

[Julien Lepiller <julien@lepiller.eu>]

Le 28 décembre 2019 05:23:18 GMT+01:00, Maxim Cournoyer <maxim.cournoyer@gmail.com> a écrit :
>Hello Znavko,
>
>znavko@disroot.org writes:
>
>> ffmpeg was installed:
>>
>
>[...]
>
>> Those two video are working (cause youtube had converted them, I
>think).
>>
>> On the other videos that are not displaying and often this is live
>streams (I think, youtube did not converted them to acceptable format)
>> these Javascript warnings with WebGL errors appear in terminal:
>>
>> https://www.youtube.com/watch?v=9K26GI4C3uY
>>
>> $ icecat
>> JavaScript error: resource:///modules/sessionstore/SessionStore.jsm,
>line 1325: uncaught exception: 2147746065
>> JavaScript warning:
>https://mail.disroot.org/rainloop/v/1.12.1/static/js/min/openpgp.min.js,
>line 0: Successfully compiled asm.js code (total compilation time 94ms)
>> JavaScript warning:
>https://mail.disroot.org/rainloop/v/1.12.1/static/js/min/openpgp.min.js,
>line 0: Successfully compiled asm.js code (total compilation time 7ms)
>> JavaScript warning:
>https://mail.disroot.org/rainloop/v/1.12.1/static/js/min/openpgp.min.js,
>line 0: Successfully compiled asm.js code (total compilation time 2ms)
>> console.warn: LoginRecipes: "getRecipes: falling back to a
>synchronous message for:" "https://www.youtube.com"
>> JavaScript warning:
>https://www.youtube.com/yts/jsbin/player_ias-vfl22ubNH/ru_RU/base.js,
>line 5359: Error: WebGL warning: getContext: Disallowing antialiased
>backbuffers due to blacklisting.
>> JavaScript warning:
>https://www.youtube.com/yts/jsbin/player_ias-vfl22ubNH/ru_RU/base.js,
>line 5359: Error: WebGL warning: <SetDimensions>: Failed to create
>WebGL context: WebGL is currently disabled.
>> JavaScript warning:
>https://www.youtube.com/yts/jsbin/player_ias-vfl22ubNH/ru_RU/base.js,
>line 5359: Error: WebGL warning: getContext: Disallowing antialiased
>backbuffers due to blacklisting.
>> JavaScript warning:
>https://www.youtube.com/yts/jsbin/player_ias-vfl22ubNH/ru_RU/base.js,
>line 5359: Error: WebGL warning: <SetDimensions>: Failed to create
>WebGL context: WebGL is currently disabled.
>> JavaScript warning:
>https://www.youtube.com/yts/jsbin/player_ias-vfl22ubNH/ru_RU/base.js,
>line 5359: Error: WebGL warning: getContext: Disallowing antialiased
>backbuffers due to blacklisting.
>> JavaScript warning:
>https://www.youtube.com/yts/jsbin/player_ias-vfl22ubNH/ru_RU/base.js,
>line 5359: Error: WebGL warning: <SetDimensions>: Failed to create
>WebGL context: WebGL is currently disabled.
>>
>>
>> Icecat console displays:
>> Error: WebGL warning: getContext: Disallowing antialiased backbuffers
>due to blacklisting. base.js:5359:276
>> Error: WebGL warning: <SetDimensions>: Failed to create WebGL
>context: WebGL is currently disabled. base.js:5359:276
>> Blocked https://www.youtube.com/watch?v=9K26GI4C3uY from extracting
>canvas data because no user input was detected. base.js:2900:157
>>
>> and many ties this:
>> Request to access cookie or storage on
>>
>“https://i.ytimg.com/vi/sfw1IB58HYA/hqdefault.jpg?sqp=-oaymwE…qpAwsIARUAAIhCGAFwAQ==&rs=AOn4CLDPtI4kQ5jl0Nq6M8f7wUF2sjlv6g”
>> was blocked because we are blocking all third-party storage access
>> requests and content blocking is enabled.
>
>I can reproduce the problem; it seems that WebGL is now a required by
>youtube when using Icecat 68? That's strange because the same video
>plays fine in an older version of Icecat (but I have to reload the page
>to get it playing).
>
>Anyway, the problem seems to have more to do with Youtube than HTML5
>playback in Icecat.  A random HTML5 video playback test site [0] may
>help to convince you of such :-)
>
>You could try enabling WebGL in your Icecat (disabled by default) by
>visiting the "IceCat-specific privacy settings" of the Settings page
>and
>checking "Enable WebGL".  That didn't work for me, as my driver seems
>blacklisted by Mozilla.  I tried force enabling it with suggestions
>from
>this page [1] but your link would still wouldn't be happy with my WebGL
>support.
>
>HTH,
>
>Maxim
>
>[0]  https://tekeye.uk/html/html5-video-test-page
>[1] 
>https://developer.mozilla.org/en-US/docs/Mozilla/QA/Graphics_Blocklisting

It's not blacklisted, it's blocked by mozilla's sandbox pplicy. In about:config you can change an option named sandbox.readpath.whitelist or similar. Set it to /gnu/store/ (with a trailing / which means recursively) to allow access to the store, where icecat can find its webgl libraries. Then restart the browser.

We should add that by default (or something more restrictive) but I don't know how.