Bug 231495 - On iOS 15, when the canvas font is set to -apple-system, calling fillText with Chinese characters would cause the whole canvas area to blank.
Summary: On iOS 15, when the canvas font is set to -apple-system, calling fillText wit...
Status: RESOLVED DUPLICATE of bug 230187
Alias: None
Product: WebKit
Classification: Unclassified
Component: Canvas (show other bugs)
Version: Safari 15
Hardware: iPhone / iPad Unspecified
: P2 Blocker
Assignee: Nobody
URL:
Keywords: HTML5
Depends on:
Blocks:
 
Reported: 2021-10-10 20:30 PDT by luonan.666
Modified: 2021-10-11 09:42 PDT (History)
4 users (show)

See Also:

Attachments
render blank demo (511 bytes, text/html)
2021-10-10 20:30 PDT, luonan.666 		no flags Details
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Description luonan.666 2021-10-10 20:30:52 PDT 
Created attachment 440751 [details]
render blank demo

On iOS 15, when the canvas font is set to -apple-system, calling fillText with Chinese characters would cause the whole canvas area to blank.

first, set ctx.font = '28px -apple-system';
and then, draw some chinese, ctx.fillText('你好', 10, 50); 
then the whole canvas area becomes blank. but English letters could render correctly. 

Just change the font-family to 'Arial', everything works fine.
Comment 1 Alexey Proskuryakov 2021-10-11 09:20:45 PDT 
I cannot reproduce this with OS 15.1 beta. I think that it was a known issue, but cannot find the bug to dupe to.
Comment 2 Wenson Hsieh 2021-10-11 09:42:08 PDT 
Likely, 230187.

*** This bug has been marked as a duplicate of bug 230187 ***