Katex renderer duplicates the expressions in description preview and during some copy/paste operations

[Blind4Basics]

Describe the bugs

Not sure if it's old or new, but the renderer is litterally acting, here:

• [x] when previewing a description (I'm forking a kata, in the capture below) all katex expressions are tripled. This occurs with any kind of katex expressions (inline and blocks)

  

• [ ] I got similar problems when solving a kata. I did a copy/paste from a description to the editor in a trainer: the description looks fine, but once the selected text has been pasted, I got triplets of it in the trainer in some situations. It looks like it happens only when copying inline katex expressions. Example here (warning: trainer link!) https://www.codewars.com/kata/56347fcfd086de8f11000014/train/typescript

  • select the whole inline expression A0​(x0​,y0​) (3rd §) and paste in the trainer => triplets: A0(x0,y0) A_0 (x_0, y_0) A0​(x0​,y0​)
  • select a whole inline expression with text surrounding it (before or after or both) + paste => triplets
  • select a part of it only + paste => ok
  • select a part of the katex block just above or a complete line of it or the whole block + paste => ok

NOTE:

once the fork is published, the description looks fine (but cause the copy/paste troubles)

┆Issue is synchronized with this Clickup by Unito

[kazk]

The first one is caused by katex.min.css not included on that page, so the preview is showing elements that's supposed to be hidden by it.

I think the second one has something to do with KaTeX outputting HTML and MathML (for accessibility). Selecting a paragraph copies both text? Not sure about this one.

[Blind4Basics]

Selecting a paragraph copies both text?

from the same kata/description, copying in the trainer:

// copying the full line (which is a §):

The starting point A0(x0,y0) A_0 (x_0, y_0) A0​(x0​,y0​) is known as well as the slope to the curve at A0 A_0 A0​ and then the tangent line at A0 A_0 A0​ .

// copying a full § with extra text before and after:

−2x.

For each xk x_k xk​ we are able to calculate the yk y_k yk​ as well as the values zk z_k zk​ of the exact solution.

Our task

It looks like the $ "tags" were replaced by the expression itself (makes me think to regex matches)

[kazk]

It shouldn't have anything to do with the original input text because only the text inside $ and math block are passed to KaTeX.

Look at the HTML it generated. It should have mathml and some spans. I thought selecting a paragraph selects both of them and the text content is copied.

[kazk]

Probably https://github.com/KaTeX/KaTeX/issues/645

[kazk]

The first one should be fixed.

[kazk]

Using the copy-tex extension should fix the second issue. But it doesn't work properly on Codewars because we use DOMPurify to sanitize the generated HTML, and <annotation> element used by that extension is filtered because it can be unsafe (https://github.com/cure53/DOMPurify/issues/673).

Not sure what can be done.

[Blind4Basics]

as long as the vizual is ok, I guess it can stay like this...