537080 - Corruption of text in wikipedia

Status: RESOLVED INVALID

(Core :: Layout: Text and Fonts, defect)

Description

[fawer]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.1.6) Gecko/20091201 Firefox/3.5.6 (.NET CLR 3.5.30729)
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.1.6) Gecko/20091201 Firefox/3.5.6 (.NET CLR 3.5.30729)

Exactly as described. Reproducible very seldom and I have only ever seen it on wikipedia. I have only seen it when there are special characters but I have only seen it at most 4 times, so I do not know if that is related.

http://img513.imageshack.us/img513/9232/renderingerror.png
This error goes away after scrolling.

http://img6.imageshack.us/img6/2805/renderingerror2.png
http://img692.imageshack.us/img692/4471/renderingerror3.png
This error goes away after refreshing, but scrolling does not fix it. It might go away after switching tabs, but I am not sure. Mousing over the links puts the links on top of the text.

Fonts:
Proportional: Sans-serif 18
Serif: Verdana
Sans-serif: Arial
Monospace: Fixedsys 13

Reproducible: Sometimes

Comment 1

[Ria Klaassen (not reading all bugmail)]

Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv:1.9.1.7pre) Gecko/20091220 Shiretoko/3.5.7pre

This is how I see the page with your settings:
http://img402.imageshack.us/img402/6026/wiki.jpg

Comment 2

[David Baron :dbaron: (⌚️UTC-5, no longer working on Mozilla)]

The screenshot makes it look like we might be taking different text painting codepaths depending on whether the *text within the region to be painted* has Chinese characters or missing characters in it.  (It's ok to take different codepaths based on what's in the textrun, but not based on what's being invalidated.)  Is that possible?