Burmese font not rendered properly with Hardware Acceleration enabled

[ZFR77]

If I have Hardware Acceleration enabled, Burmese script does not get rendered properly. See attached. It works fine if I disable Hardware Acceleration.

I've got the following font installed
https://software.sil.org/padauk/

Is there any way to get this fixed. I don't want to disable hardware acceleration.

Thanks.

[Moonchild]

Is there anything related mentioned in the browser console/error console when you try to load the page with HWA enabled?

Also, please include the information in Help -> troubleshooting information (button "Copy as text")

[ZFR77]

Is there anything related mentioned in the browser console/error console when you try to load the page with HWA enabled?

Also, please include the information in Help -> troubleshooting information (button "Copy as text")

Thanks.

I could find nothing illuminating relating to this in the console. The page in question is
https://en.wikipedia.org/wiki/Burmese_language
But it happens in many other pages that contain Burmese scipt (also noticed it happens to some other Asian scripts)

The troubleshooting information is as follows:

Code: Select all

Application Basics
------------------

Name: Pale Moon
Version: 27.7.2
Build ID: 20180130115844
Update Channel: release
User Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:52.9) Gecko/20100101 Goanna/3.4 Firefox/52.9 PaleMoon/27.7.2
OS: Windows_NT 6.1
Multiprocess Windows: 0/1 (default: false)
Safe Mode: false

Extensions
----------

Name: Adblock Latitude
Version: 4.0.1
Enabled: true
ID: adblocklatitude@addons.palemoon.org

Name: Add Bookmark Helper
Version: 1.0.2
Enabled: true
ID: abh2me@Off.JustOff

Name: Old Default Image Style
Version: 3.0.6.1-signed.1-signed
Enabled: true
ID: olddefaultimagestyle@dagger2-addons.mozilla.org

Graphics
--------

Adapter Description: NVIDIA GeForce GTX 970
Adapter Drivers: nvd3dumx,nvwgf2umx,nvwgf2umx nvd3dum,nvwgf2um,nvwgf2um
Adapter RAM: 4095
ClearType Parameters: Gamma: 2200 Pixel Structure: R ClearType Level: 100 Enhanced Contrast: 50
Device ID: 0x13c2
Direct2D Enabled: true
DirectWrite Enabled: true (6.2.9200.22164)
Driver Date: 1-3-2018
Driver Version: 23.21.13.9065
GPU #2 Active: false
GPU Accelerated Windows: 1/1 Direct3D 11 (OMTC)
Subsys ID: 366f1458
Vendor ID: 0x10de
WebGL Renderer: Google Inc. -- ANGLE (NVIDIA GeForce GTX 970 Direct3D11 vs_5_0 ps_5_0)
windowLayerManagerRemote: true
AzureCanvasBackend: direct2d 1.1
AzureContentBackend: direct2d 1.1
AzureFallbackCanvasBackend: cairo
AzureSkiaAccelerated: 0

Important Modified Preferences
------------------------------

accessibility.typeaheadfind.flashBar: 0
browser.cache.disk.capacity: 358400
browser.cache.disk.smart_size.first_run: false
browser.cache.disk.smart_size.use_old_max: false
browser.display.standalone_images.background_color: #ffffff
browser.download.importedFromSqlite: true
browser.places.smartBookmarksVersion: 4
browser.startup.homepage: https://gamefaqs.gamespot.com
browser.startup.homepage_override.buildID: 20180130115844
browser.startup.homepage_override.mstone: 3.4.2
browser.tabs.warnOnClose: false
browser.tabs.warnOnCloseOtherTabs: false
extensions.lastAppVersion: 27.7.2
font.internaluseonly.changed: false
gfx.direct3d.last_used_feature_level_idx: 0
image.http.accept: image/webp,image/jxr,image/png,image/*;q=0.8,*/*;q=0.5
network.cookie.prefsMigrated: true
places.database.lastMaintenance: 1517968430
places.history.expiration.transient_current_max_pages: 104858
privacy.sanitize.migrateFx3Prefs: true
storage.vacuum.last.index: 1
storage.vacuum.last.places.sqlite: 1517361500

Important Locked Preferences
----------------------------

Places Database
---------------

JavaScript
----------

Incremental GC: true

Accessibility
-------------

Activated: false
Prevent Accessibility: 1

Library Versions
----------------

NSPR
Expected minimum version: 4.16
Version in use: 4.16

NSS
Expected minimum version: 3.32.1
Version in use: 3.32.1

NSSSMIME
Expected minimum version: 3.32.1
Version in use: 3.32.1

NSSSSL
Expected minimum version: 3.32.1
Version in use: 3.32.1

NSSUTIL
Expected minimum version: 3.32.1
Version in use: 3.32.1

Experimental Features
---------------------

[Moonchild]

I looked into this a little and it simply seems to be a case of system fonts not including the unicode characters for Burmese script. The downloaded and locally-installed font won't be used unless the website in particular indicates it as a local resource to use, which Wikipedia doesn't seem to be doing.

An update of the default serif and sans-serif fonts to include Unicode9 characters would be a solution that won't require website changes.

The strange thing is that this should be completely unrelated to hardware acceleration, because font selection is not determined by final rendering settings...?

EDIT: Maybe this support article helps https://answers.microsoft.com/en-us/win ... dd5?auth=1

[ZFR77]

An update of the default serif and sans-serif fonts to include Unicode9 characters would be a solution that won't require website changes.
The strange thing is that this should be completely unrelated to hardware acceleration, because font selection is not determined by final rendering settings...?

Changing the default fonts for "Other writing systems" to Padauk worked. Thanks.
The font is different from what I see when HWA is disabled and default font (Times New Roman + Arial) is used (I don't speak Burmese so can't comment on the difference but it seems to be difference in font only).

As far as I'm concerned my issue is solved. Unless you want to investigate further on why there is a difference between HWA disabled/enabled behaviour.

[ZFR77]

Just wanted to add, that I did some testing, and on a clean isntall without any special fonts added, Firefox displays that text fine with or without HWA enabled, while Palemoon only with HWA disabled.

[ZFR77]

Also, as mentioned it's not just Burmese script but other fonts. For example, from Wikipedia's emoji page:
https://en.wikipedia.org/wiki/Emoji#Unicode_blocks

[Moonchild]

The unicode emojis from wikipedia should now display properly on the latest unstable version (on Windows, at any rate).

[ZFR77]

Thank you.

I just tried the unstable release and it works. Did you do anything to the other fonts as well? Because Burmese and some other fonts are now displayed correctly too with HWA enabled.

EDIT:
Actually, just tested the stable release on Windows 10, and the Burmese font is rendered correctly there too. HWA enabled and disabled. Same for other fonts.

On my Windows 7 machine however, the Burmese (and some other) fonts only get displayed properly with HWA disabled, but appear as squares with HWA enabled.

[Moonchild]

Part of the change was bypassing GDI table loading for embedded fonts, which would cause an issue with DirectWrite not knowing about the glyphs otherwise.
Locally-installed fonts should be fine though, but you can always see if switching the about:config preference "gfx.font_rendering.directwrite.use_gdi_table_loading" to "false" solves your problem on Windows 7.

[ZFR77]

So unfortunately it turns out the unstable version didn't solve the font problem on Windows 7. Emojis appear correctly. But Burmese and other other fonts (e.g. Cuneiform, Cherokee, Tai Viet, Avestan; I can compile a more comprehensive list if that would be helpful) don't.

I ensured all these fonts are installed. And they do appear correctly as soon as HWA is switched off (and also in Firefox).

Changing the default font in "Other writing systems" to a particular font will work for that particular font.

Also, changing gfx.font_rendering.directwrite.use_gdi_table_loading has no effect.

And again, this is not anything urgent for me; I don't use all these fonts. Just drawing your attention to this in case it's something you'd want to look into.