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Denne tråden ble arkivert. Still et nytt spørsmål dersom du trenger hjelp.

[regression] Text rendering is incorrect

PiotrGrochowski
PiotrGrochowski
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Those three operations should make the text rendering correct:

Disable hardware acceleration Set gfx.canvas.azure.backends to direct2d1.1,cairo Set gfx.content.azure.backends to direct2d1.1,cairo

https://renderingenginetest.netlify.com/

Dark theme can be tested by reversing the foreground and background colors in the HTML.

For reference, here is the correct GDI rendering of this website:

https://i.imgur.com/dWuZfbD.png https://i.imgur.com/M4oKd7i.png

In Firefox ESR 52.4.1 (32-bit), text renders correctly:

https://i.imgur.com/InrXmeI.png https://i.imgur.com/kn3bZra.png

which is the same as the GDI rendering of this website, except for some line spacing issues.

However, in Firefox 70.0b6 (32-bit), the rendering regressed and text no longer renders correctly:

https://i.imgur.com/Jn2NxGJ.png https://i.imgur.com/qDxww7y.png

Line spacing is correct, but don't let this distract you from how profoundly unsmooth the rendering is in the light theme version. The dark theme version is nearly identical though.

Those three operations should make the text rendering correct: Disable hardware acceleration Set gfx.canvas.azure.backends to direct2d1.1,cairo Set gfx.content.azure.backends to direct2d1.1,cairo https://renderingenginetest.netlify.com/ Dark theme can be tested by reversing the foreground and background colors in the HTML. For reference, here is the correct GDI rendering of this website: https://i.imgur.com/dWuZfbD.png https://i.imgur.com/M4oKd7i.png In Firefox ESR 52.4.1 (32-bit), text renders correctly: https://i.imgur.com/InrXmeI.png https://i.imgur.com/kn3bZra.png which is the same as the GDI rendering of this website, except for some line spacing issues. However, in Firefox 70.0b6 (32-bit), the rendering regressed and text no longer renders correctly: https://i.imgur.com/Jn2NxGJ.png https://i.imgur.com/qDxww7y.png Line spacing is correct, but don't let this distract you from how profoundly unsmooth the rendering is in the light theme version. The dark theme version is nearly identical though.

All Replies (6)

TyDraniu
TyDraniu
  • Top 25 Contributor
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PiotrGrochowski said

Those three operations should make the text rendering correct: Disable hardware acceleration Set gfx.canvas.azure.backends to direct2d1.1,cairo Set gfx.content.azure.backends to direct2d1.1,cairo

If you disabled HA, enumerating 'direct2d1.1' was redundant. You've been using cairo for text rendering.

Recently cairo code has been removed from the browser. See bug 1517077.

PiotrGrochowski
PiotrGrochowski Eieren av spørsmålet
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What a facepalm it is that high quality text rendering has been removed. It is a regression. It is a dealbreaker because many if not most webpages have text in them so I'm not using the recent version.

McCoy
McCoy
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See this Reddit thread :

https://www.reddit.com/r/firefox/comments/cz6nys/firefox_69_breaks_windows_font_rendering/

PiotrGrochowski
PiotrGrochowski Eieren av spørsmålet
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Has anyone tested whether this regression is crossplatform? (all platforms using Mozilla's open-source DirectWrite renderer as opposed to the system native text rendering engine)

Endret av PiotrGrochowski

PiotrGrochowski
PiotrGrochowski Eieren av spørsmålet
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https://fontgammatest.netlify.com/ is the test of gamma.

PiotrGrochowski
PiotrGrochowski Eieren av spørsmålet
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To this day, Firefox ESR 52.4.1 (32-bit) is one of the only browsers to even remotely allow standard GDI rendering.