Firefox on Android 4.4 doesn't correctly show some utf-8/emoji




Firefox for Android
4 years ago
2 years ago


(Reporter: paulv, Unassigned)


({reproducible, testcase})

28 Branch
reproducible, testcase
Dependency tree / graph

Firefox Tracking Flags

(Not tracked)




(2 attachments)



4 years ago
User Agent: Mozilla/5.0 (X11; Linux i686; rv:25.0) Gecko/20100101 Firefox/25.0 (Beta/Release)
Build ID: 20131112160018

Steps to reproduce:

I browsed to

Actual results:

On Android 4.4 (Nexus 7 2013), using Firefox 25.0.1 and Firefox Beta, downloaded from the Google Play Store, the line with the utf-8/emoji is rendered incorrectly.

On Android 4.3 (Nexus 7 2013), using Firefox 25.0.1, the line with the utf-8/emoji was rendered correctly (I upgraded the device, so I can't test it in 4.3).

On Android 4.1.2 (Samsung Galaxy S3), using Firefox 25.0.1, the line with the utf-8/emoji is rendered correctly.

The bug is a bit odd. It seems to delete the previous characters on the line. View source on the page to see what the line should look like.

Expected results:

The page should render correctly.
I see this on my Nexus 5 as well (tested with Nightly 28.0).
Ever confirmed: true
Keywords: reproducible, testcase
OS: Linux → Android
Hardware: x86 → ARM
Version: Firefox 25 → Firefox 28
Simple test-case: data:text/plain;charset=UTF8,%F0%9F%90%B1
Could you attach a screenshot showing the incorrect rendering, please?

Comment 4

4 years ago
Created attachment 8340948 [details]
Screenshot from Firefox 25.0.1 on Android 4.4
I have the Nexus 7 2012 Android 4.4 "KitKat" /system/fonts/ folder at

Comment 6

4 years ago
Created attachment 8347923 [details]
Chrome on Android 4.4

Chrome doesn't get this test case right either, but it does manage to show the text that Firefox doesn't (But fails at the Emoji as well)
Hmm - looks like the 4.4 /system/fonts/ folder (from comment 5) includes Google's "Noto Color Emoji" font, which uses their new (and not standardized) format to embed color bitmaps. I suspect that's probably triggering the problem, although I'm not sure why - even if we can't render that font (which requires a pretty recent version of FreeType, at least), it shouldn't affect the rest of the text.
Support for the color emoji font is bug 974575 and bug 969814.

I believe the other missing (non-emoji) text was bug 973380, which should now be fixed on trunk.
Depends on: 974575, 969814, 973380
You need to log in before you can comment on or make changes to this bug.