Mathjax not rendering properly on iPadOS 26

[GrumpyPanda]

I updated my iPad to iPadOS 26.2 yesterday, and ever since then the MathJax formulas are no longer rendering properly.

Here’s a screenshot of one such case:

It renders properly on Anki 25.02.5 for MacOS and AnkiMobile on iOS 18.7.3:

This is not just limited to subscripts, though it seems like it’s always some upper portion of symbols that is missing.

[Danika_Dakika]

1. Give us the exact text from the HTML view of that field (click </> or < > to see that), or from your card template (if that’s where this is) – as text, please – so that folks can try to reproduce this.

2. Are you using AnkiMobile 25.09 on both iOS and iPadOS? [ Preferences > About]

[GrumpyPanda]

I just checked, and I am on AnkiMobile 25.09 on both iOS and iPadOS.

I don’t remember exactly which card the above screenshot is from, so here is another one that’s not rendering properly:

Full content of the HTML field:

<anki-mathjax>\large
\begin{bmatrix}
\underline{A}_1 &amp; &amp; \\
&amp; \ddots &amp; \\
&amp; &amp; \underline{A}_n
\end{bmatrix}</anki-mathjax>

EDIT - Just realized the HTML field format slightly differs on AnkiMobile, so here’s that as well just in case:

\(\large
\begin{bmatrix}
\underline{A}_1 & & \\
& \ddots & \\
& & \underline{A}_n
\end{bmatrix}\)

What it looks like on iPadOS 26.2:

What it looks like on iOS 18.7.3:

It seems like this happens irregardless of card template, but just for completeness, a basic card template for which this renders improperly on iPadOS 26.2, both on front and back:

Front Template:

{{Front}}

Back Template:

{{Front}}

<hr id=answer>
<hr id=answer>

{{Back}}

Styling:

.card {
 font-family: arial;
 font-size: 20px;
 text-align: left;
 color: black;
 background-color: white;
}

[abdo]

It’s possible that an OS update broke this, because AnkiMobile relies on the built-in web engine to render cards.

[GrumpyPanda]

While doing my reviews today I discovered that zooming in on a formula that didn’t render properly can make it show as intended. Still a bit bothersome, but at least I don’t have to guess at my formulas anymore

[vanheyden]

I have the same issue it seems the recent iOS update broke the rendering. I also discovered the zoom trick. Still annoying though

[abdo]

Logged here:

Mathjax rendering issue after recent iOS update

[GrumpyPanda]

@vanheyden

I have the same issue

Did you happen to notice any patterns in the cards for which this issue occurs? I’m starting to think that, in my case, it might be limited to \underline (and possibly \overline{}), but it could very well be that others are broken too and I’m simply not using them.