Make sure OffScreenCanvas API does not render moot our canvas fingerprinting protection

There is a new OffScreenCanvas API that allows running WebGL in web workers (e.g.). This is currently preffed of (ESR45) (gfx.offscreencanvas.enabled is set to false). But this sounds scary enough that we want to make sure that

a) preffing off the feature renders it really unusable (we should do this for esr45)

and

b) if it is preffed on our canvas fingerprinting protections are not harmed (can be checked when we transtions to an esr with this feature enabled).

added GeorgKoppen201705 TorBrowserTeam201711 component::applications/tor browser ff78-esr owner::tbb-team priority::high severity::normal sponsor::44-can status::new tbb-fingerprinting type::task labels

Trac:
Keywords: N/A deleted, tbb-6.0a5 added

Taking ownership of some ff45-esr tickets.

Trac:
Status: new to accepted
Owner: tbb-team to mcs

Trac:
Cc: N/A to brade

Kathy and I reviewed the implementation of this feature and also ran some manual tests. We are convinced that this feature is fully disabled by the gfx.offscreencanvas.enabled = false setting, so we should be OK for ESR45. I suggest changing the keywords field on this ticket to ff52-esr.

It is also worth noting that Mozilla's automated tests for offscreen canvas are in dom/canvas/test/test_offscreencanvas*.html but they always set gfx.offscreencanvas.enabled = true.

Thanks, doing so.

Trac:
Owner: mcs to tbb-team
Keywords: tbb-6.0a5, ff45-esr deleted, ff52-esr added
Status: accepted to assigned

Remaining things for offscreen canvas got implemented: https://bugzilla.mozilla.org/show_bug.cgi?id=1172796. That feature is still behind a pref and disabled but we should make sure that the new things are respecting it as well.

Trac:
Sponsor: N/A to Sponsor4

Adding tickets to our 7.0 ticket list

Trac:
Keywords: N/A deleted, tbb-7.0-must added

Getting more tickets on our alpha radar.

Trac:
Keywords: tbb-7.0-must deleted, tbb-7.0-must-alpha added

Moving the investigation tickets to higher priority.

Trac:
Priority: Medium to High

Trac:
Keywords: N/A deleted, tbb-fingerprinting added

Moving more tickets on our May 2015 radar.

Trac:
Keywords: N/A deleted, TorBrowserTeam201705 added

We are beyond the alpha testing. Moving tickets for tbb-7.0-must.

Trac:
Keywords: tbb-7.0-must-alpha deleted, tbb-7.0-must added

Trac:
Keywords: N/A deleted, GeorgKoppen201705 added
Owner: tbb-team to gk

Looking over the changes in https://bugzilla.mozilla.org/show_bug.cgi?id=1172796 I think they still adhere to the preference being disabled in ESR52. Thus, we can move the real work in determining the fingerprinting issues at least to ff59-esr.

Trac:
Owner: gk to tbb-team
Keywords: tbb-7.0-must, ff52-esr deleted, ff59-esr added

Moving our tickets to June.

Trac:
Keywords: TorBrowserTeam201705 deleted, TorBrowserTeam201706 added

Moving Tickets to July 2017.

Trac:
Keywords: TorBrowserTeam201706 deleted, TorBrowserTeam201707 added

Moving our Tickets to August.

Trac:
Keywords: TorBrowserTeam201707 deleted, TorBrowserTeam201708 added

Items for September 2017.

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Keywords: TorBrowserTeam201708 deleted, TorBrowserTeam201709 added

Items for October 2017

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Keywords: TorBrowserTeam201709 deleted, TorBrowserTeam201710 added

Moving tickets over to November.

Trac:
Keywords: TorBrowserTeam201710 deleted, TorBrowserTeam201711 added

See: https://bugzilla.mozilla.org/show_bug.cgi?id=1422862.

Firefox 60 is the new ESR.

Trac:
Keywords: ff59-esr deleted, ff60-esr added

Seems this has time at least until Firefox 68 ESR. OffScreenCanvas is not defined in ESR 60 (unless one flips the pref mentioned in the comment:description. See: https://lyuyuan92.github.io/test_canvas_on_and_off_screen.html for a demo.

Trac:
Keywords: ff60-esr deleted, ff68-esr added

Adding Sponsor 44 to ESR68 tickets

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Sponsor: Sponsor4 to Sponsor44-can

Still off in ESR68.

Trac:
Keywords: ff68-esr deleted, N/A added

Trac:
Keywords: N/A deleted, ff76-esr added
Status: assigned to new

ff76-esr? https://hacks.mozilla.org/2019/09/moving-firefox-to-a-faster-4-week-release-cycle/

There is no 76 ESR.

Trac:
Keywords: ff76-esr deleted, ff78-esr added

Here is the offscreen canvas meta bug

• https://bugzilla.mozilla.org/show_bug.cgi?id=1390089

My understanding is that the pref will be removed: see comment 0 (emphasis mine)

We don't seem to have a metabug tracking the remaining work to be able to ship unpreffed, so here is one

mentioned in issue #19048 (moved)

mentioned in issue #20680 (moved)

moved to tpo/applications/tor-browser#18599 (closed)