Windows has a system to set font aliases through the registry.
This allows some customization that could be used as a fingerprinting
vector.
Moreover, this mechanism is used by Windows itself, and different SKUs
might have different default FontSubstitutes.

The mechanism to choose the UI font does not play well with our
fontconfig configuration. As a result, the final criterion to choose
the font for the UI was its version.

Since we hardcode Arimo as a default sans-serif on preferences, we use
it also for the UI. FontConfig will fall back to some other font for
scripts Arimo does not cover as expected (we tested with Japanese).

Bug 42529: Fix the breakage of this patch on Android.

Also, improve the patch hoping I can finally uplift it.

System fonts are an enormous fingerprinting vector.
Even with font allow lists and with our custom configuration on Linux,
which counter metrics measurements, getComputedStyle leaks several
details.
This patch counters both these kinds of attacks.

Tom Ritter authored 1 year ago and Pier Angelo Vendrame committed 10 months ago

Differential Revision: https://phabricator.services.mozilla.com/D204571

Bob Owen authored 1 year ago and Pier Angelo Vendrame committed 10 months ago

This also specializes ElementStreamFormat for bool.

Differential Revision: https://phabricator.services.mozilla.com/D187794

Original Revision: https://phabricator.services.mozilla.com/D208657

Differential Revision: https://phabricator.services.mozilla.com/D208837

Original Revision: https://phabricator.services.mozilla.com/D208556

Differential Revision: https://phabricator.services.mozilla.com/D208836

Original Revision: https://phabricator.services.mozilla.com/D203973

Differential Revision: https://phabricator.services.mozilla.com/D206555

Differential Revision: https://phabricator.services.mozilla.com/D205993

Original Revision: https://phabricator.services.mozilla.com/D204918

Differential Revision: https://phabricator.services.mozilla.com/D206179

Bug 1874489 - patch 2 - Avoid potential arithmetic overflow during Buffer read operations.  a=RyanVM

Original Revision: https://phabricator.services.mozilla.com/D204917

Differential Revision: https://phabricator.services.mozilla.com/D206178

This is just https://github.com/khaledhosny/ots/pull/277 from upstream, not really part
of this issue but touching the same code, so simplest to include it here.

Original Revision: https://phabricator.services.mozilla.com/D204916

Differential Revision: https://phabricator.services.mozilla.com/D206096

So as to not change load timing from stylo threads.

Differential Revision: https://phabricator.services.mozilla.com/D203927

Bug 1879825 - Make Family::FindIndex fallible and safely handle failures. r=gfx-reviewers,lsalzman, a=dsmith

Differential Revision: https://phabricator.services.mozilla.com/D201819

Bug 1855686 - [bug 1877341 on esr115] Reset GLContext TLS current-context caching when calling library MakeCurrent symbols.  a=RyanVM

Original Revision: https://phabricator.services.mozilla.com/D200866

Differential Revision: https://phabricator.services.mozilla.com/D201001

Differential Revision: https://phabricator.services.mozilla.com/D199380

The DirectWrite "bold simulation" has poor results with some fonts;
we already disable it by default for webfonts, to avoid rendering
issues.

As it also works poorly with some of the component layers in Segoe UI
Emoji, let's disable it for COLR fonts as well.

Bug 1878182 - Instantiate Cairo scaled font for ScaledFontBase::GetPathForGlyphs. r=jfkthameApproved for 123 beta 8, thanks. a=pascalc

This bug likely dates back to bug 1584268, which makes it so that Cairo scaled fonts must be
instantiated on demand for their first use. It seems like some StrokeGlyphs machinery got
overlooked and somehow never caused a problem till now.

Differential Revision: https://phabricator.services.mozilla.com/D200472

Differential Revision: https://phabricator.services.mozilla.com/D200784

Original Revision: https://phabricator.services.mozilla.com/D199035

Differential Revision: https://phabricator.services.mozilla.com/D199374

Differential Revision: https://phabricator.services.mozilla.com/D198163

Differential Revision: https://phabricator.services.mozilla.com/D198046

Differential Revision: https://phabricator.services.mozilla.com/D198114

Original Revision: https://phabricator.services.mozilla.com/D192039

Differential Revision: https://phabricator.services.mozilla.com/D195330

Original Revision: https://phabricator.services.mozilla.com/D194368

Differential Revision: https://phabricator.services.mozilla.com/D194434

Bug 1721612 - Fix AdjustAdvancesForSyntheticBold to reliably handle negative adjustments. r=gfx-reviewers,lsalzman a=RyanVM

This method (as its name suggests) was originally created to handle synthetic-bold,
which only ever increases the advance, and so its use of an unsigned value for the
adjustment worked ok.

But when applying tracking, the adjustment may be negative, and assigning this to
a uint32_t value takes us into undefined-behavior territory. It seems this worked
"as expected" on x86_64 (using modulo arithmetic), but on arm64 the value just
clamped to zero, and the intended negative tracking doesn't get applied.

Making it an int32_t results in consistent behavior across both architectures.

Differential Revision: https://phabricator.services.mozilla.com/D193288

Bug 1862182 - Create a pref to allow font fallback for unassigned Unicode codepoints. r=gfx-reviewers,lsalzman, a=dsmith

Differential Revision: https://phabricator.services.mozilla.com/D192451

Bug 1854090 - Omit psnames of fonts with family-name *.tmp from src:local() lookups on Windows. r=jwatt, a=dsmith

This is a sad hack, but aims to work around the issue that some
PDF-related software (Acrobat is suspected but not currently confirmed)
is potentially polluting the global font collection with re-encoded
subsets of standard fonts like Arial, but does not munge the psname;
these can then be returned by src:local(...) lookups, which results in
garbled or missing text.

In principle, if such fonts are "installed", Firefox is not wrong to use
them; it's just a badly-configured system. But given that it seems to be
caused by some PDF-handling software, without the user's knowledge, it
seems worth trying to avoid the problem. Simply skipping the psname of
any font with family-name *.tmp is highly unlikely to adversely affect
any real-world content.

Differential Revision: https://phabricator.services.mozilla.com/D191639

Differential Revision: https://phabricator.services.mozilla.com/D191813

In the case where the LayerTreeState for the input content LayersID
was found, but its mParent was null for some reason, the function
was incorrectly returning the content LayerTreeState.

Instead, in such a case, where the root LayerTreeState cannot be
looked up, the function should return null.

Original Revision: https://phabricator.services.mozilla.com/D190143

Differential Revision: https://phabricator.services.mozilla.com/D192278

Bug 1658432: Don't remove wrapping CALayer from its superview outside of Commit. r=mac-reviewers,mstange, a=dsmith

This change lets NativeLayerRootCA::Representation::Commit be the only
point where sublayers are added and removed from the root CALayer.

Differential Revision: https://phabricator.services.mozilla.com/D191673

Bug 1859591 - Add gfxCriticalNote when failing to load EGL/GLES DLLs on Windows. r=gfx-reviewers,jrmuizel a=RyanVM

Differential Revision: https://phabricator.services.mozilla.com/D191206

Bug 1856035 - Rework the management of font variation settings across CoreGraphics and CoreText font instances, on macOS 13 and later only. r=gfx-reviewers,lsalzman, a=dmeehan

Differential Revision: https://phabricator.services.mozilla.com/D191124

Depends on D191123

Bug 1856035 - Merge implementations of CreateCTFontFromCGFontWithVariations from gfxMacFont.cpp and 2d/ScaledFontMac.cpp (no change in behavior). r=gfx-reviewers,lsalzman, a=dmeehan

Differential Revision: https://phabricator.services.mozilla.com/D191123

Differential Revision: https://phabricator.services.mozilla.com/D188617

This varying's precision being reduced to mediump in bug bug 1823411
is causing rendering glitches on certain Mali devices. It should never
have been reduced in the first place, as calculations regarding
positions may require the extra precision. This patch therefore
reverts it to highp.

Differential Revision: https://phabricator.services.mozilla.com/D188984

Differential Revision: https://phabricator.services.mozilla.com/D189243