Closed Bug 852198 Opened 10 years ago Closed 3 years ago

Unicode mathematical symbols rendered as grey rectangles


(Firefox for Android Graveyard :: General, defect)

Not set


(firefox19 affected, firefox20 affected, firefox21 affected, firefox22 affected)

Tracking Status
firefox19 --- affected
firefox20 --- affected
firefox21 --- affected
firefox22 --- affected


(Reporter: cpeterson, Unassigned)





(3 files)

Attached image Firefox_screenshot.png
1. Load
2. See the grey rectangles where there should be (smart) quotation marks

See the attached screenshot.
btw, Chrome and the JB stock browser both render the smart quotes correctly.
I don't see "smart quotes" there, what I see in those places (viewing the page on desktop) are "⟨" and "⟩", which are U+27E8/27E9 from one of the Unicode mathematical symbols blocks.

On a Nexus 10 in Firefox, I see gray boxes, suggesting we don't find a font for those. And in Chrome on the same device, I see...blanks. But not quotes.
oops! You are correct. This problem is not about smart quotes.
Summary: Smart quotes rendered as grey rectangles → Unicode mathematical symbols rendered as grey rectangles
Could you post a screenshot of that page in Chrome and/or stock browser on your device?
Attachment #726227 - Attachment description: Smart_quotes_screenshot.png → Firefox_screenshot.png
Attachment #726227 - Attachment filename: Smart_quotes_screenshot.png → Firefox_screenshot.png
JB stock browser screenshot.
Attached image Chrome_screenshot.png
Chrome screenshot.
Since neither Chrome nor the JB stock browser can render these Unicode symbols, is this still even a bug we should fix? Is there a better fallback character we can render a grey rectangle or, like Chrome and stock, a blank space?
OK, so this isn't a Firefox bug as such, it's a limitation of the fonts available on the device. If there were a font that supported the characters, we'd render them.

I don't think rendering -nothing- (or a small blank space, which is almost the same as "nothing" from a user's point of view) is better, in general, than a visible gray blob. It's better to show the user that there is -something- they're missing than to hide it completely. Though the gray boxes are ugly, I agree. Maybe we could just frame them instead of filling them?

For a "better" fix, we could consider adding a font to our product that includes glyphs for a wide range of the Unicode symbols that are not covered by the standard serif and sans-serif fonts. Maybe just the Regular face of DejaVu Sans - that would cover a huge number of symbols etc that are currently unavailable.

(Or if we finish up bug 619521, perhaps we could provide these via a font that is downloaded on demand.)
For comparison, I think desktop Firefox replaces missing Unicode glyphs with a rectangle (empty or containing a hex code) or a (upside-down?) question mark.
Right. The code to draw a "hexbox" is explicitly disabled on mobile (probably for performance reasons, though I guess we could revisit that).
Mass change to move Firefox for Android::Readability bugs to block bug 1129033. Filter on readability-mass-move.
Blocks: 1129033
Component: Readability → General
We have completed our launch of our new Firefox on Android. The development of the new versions use GitHub for issue tracking. If the bug report still reproduces in a current version of [Firefox on Android nightly]( an issue can be reported at the [Fenix GitHub project]( If you want to discuss your report please use [Mozilla's chat]( server and join the [#fenix]( channel.
Closed: 3 years ago
Resolution: --- → INCOMPLETE
Product: Firefox for Android → Firefox for Android Graveyard
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