[FEATURE] multiline input

Description

In order to be able to type content across multiple lines, you must add \begin{multiline} ... \end{multiline} (#190). I think it would be better if there were an option to specify if you want to enable the multiline environment natively. In Katex, just adding \\ without any environment, specifies a newline.

Actual behavior

The problem is that if you go to mathlive.io and paste \begin{multiline} \end{multiline}, you must press the left arrow in order to move the cursor in the right position. This could be solved by using mf.perform(['insert', '\\begin{multiline} #0 \\end{multiline}']); but again, if the user clicks at the right blank side of the mathfield, they would focus outside the multiline environment.

Expected Behavior

I think that allowing both multiline and regular input side to side, is of no use, so it would make sense if only one mode was allowed, for the whole mathfield, without the need for the user to manually add \begin{multiline} ... \end{multiline}.

[arnog]

Pasting \begin{multiline} ... \end{multiline} into a mathlive input doesn’t work right now on the website or the latest npm version, FWIW.

The name of the environment is multline not multiline. It’s the LaTeX spelling 🤷 and it’s working right now.

[elisaado]

This is how I’ve seen it in other editors (like microsoft Word): each time you go to a new line (by pressing the return key), a new math container is created for that line, so in this case it would be

<math-field>f(x)=...</math-field>
<br>
<math-field>g(x)=...</math-field>

(well don’t use br but some css to make each math-field span a new line)