Multiline shortcut produces invalid LaTeX

[AllyMarthaJ]

Description

When using the inline shortcut for inserting multiline content, invalid MathLive content is produced.

Steps to Reproduce

1. Go to MathLive demo at https://cortexjs.io/mathlive/demo/.
2. Enter some text, e.g. a. Then use the inline shortcut e.g. Mod-Enter and type b.
3. Copy the resultant LaTeX, refresh, and input the LaTeX into the field. (It is something of the form \begin{lines}a\\ b\end{lines})
4. Observe the MathLive field no longer renders the multiline content.

Associated screenshots:

Before:

After:

This is reproducible on an external platform too.

Actual Behavior

Invalid MathLive LaTeX is produced.

Expected Behavior

The LaTeX should be able to be re-used within the MathLive editor.

Environment

MathLive version
0.94.6

[arnog]

Fixed with e992548

[AllyMarthaJ]

This is still an issue on latest version.

[arnog]

I cannot reproduce it. Can you check you are using 0.95.0? (On the MathLive Demo page the version is indicated at the bottom of the page).

I followed the steps in the issue report. Is there something missing?

When you say "reproducible on external platform", what do you mean?

[AllyMarthaJ]

If you paste the above LaTeX on the demo page, it still fails to render with the same failure points as pictured. I was also able to replicate from scratch the same bug on the demo page.

Unless I'm misunderstanding the fix, the environment shouldn't have changed right?

[arnog]

What OS/browser are you using?

And so that we’re on the same page, the issue occurs not when following the steps in the original report, but if you copy \begin{lines}a\\ b\end{lines} and paste it into the mathfield?

[AllyMarthaJ]

Yeah; I followed the same steps as before. Just to clarify with a video:

Screen.Recording.2023-07-06.at.9.00.50.am.mov

Chrome 114.0.5735.198 (Official Build) (arm64)
macOS 13.2.1 (22D68)

[AllyMarthaJ]

As for why pasting is relevant: this same issue occurs when you programatically load in the LaTeX via setValue or otherwise (so for my usage, I have an editor, which when previewed will render the LaTeX incorrectly as above)

[arnog]

Ah, OK, I get it now. I thought you were copying and pasting from the mathfield, which was broken but is working now. I thought that was the issue.

There is indeed another issue when pasting LaTeX copied from elsewhere (or when setting the value directly). Thank you, this helps.

[AllyMarthaJ]

No, thank you! Sorry for the ambiguity haha