Bad math-related display in iOS Wikipedia app
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When viewing the Wikipedia article in the iOS Wikipedia app, there is displayed just above the section heading "S-arithmetic groups" a string that reads (as a top level heading):

'''`UNIQ--postMath-00000068-QINU`'''-arithmetic groups

The source for the heading is

== <math>S</math>-arithmetic groups ==

I presume this is some sort of error message. The problem is fully reproducible on my device. I am using an iPhone X running iOS 11.3 and there are no pending updates. The problem does not occur when viewing the same article in Safari on my iPhone nor in Safari on my MacBook.

Restricted Application added a subscriber: Aklapper. · View Herald TranscriptApr 24 2018, 3:41 PM
Restricted Application added a project: Wikipedia-iOS-App-Backlog. · View Herald TranscriptApr 24 2018, 4:43 PM
Physikerwelt added a subscriber: Physikerwelt.EditedApr 24 2018, 5:07 PM

Can you post a screenshot of the safari rendering? Safari can render MathML, and I wonder if it uses MathML or the fallback image (which I would expect).

Fig. 1: MathML rendering in Firefox (left) and SVG fallback rendering in Chromium (right)

(I do not know the iOs app.)

@Dbrant @Fjalapeno is this related/similar to the recent issue fixed on Android? I remember you mentioned in joint app teams standup, but am not sure if this is the same...

Not quite, this looks like a subtly different issue.

(To clarify, on Android this section heading appears correctly in the WebView, but doesn't appear correctly in our Table of Contents.)

In this case, the actual heading of the section contains some rather complex HTML (namely MathML with image fallback) which we're not able to render in a relatively dumb native TextView (the native TextView really expects mostly plain-text headings, with perhaps some minimal HTML, e.g. italics.)

I'm not sure what the best solution for this would be, short of writing special-case code to parse MathML content in heading titles when displaying them natively...

JMinor triaged this task as Low priority.Apr 30 2018, 5:49 PM
JMinor moved this task from Needs Triage to Product Backlog on the Wikipedia-iOS-App-Backlog board.
Vvjjkkii renamed this task from Bad math-related display in iOS Wikipedia app to 8beaaaaaaa.Jul 1 2018, 1:14 AM
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Mainframe98 renamed this task from 8beaaaaaaa to Bad math-related display in iOS Wikipedia app.Jul 1 2018, 7:50 AM
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