Using "contenteditable" in Attachments

Hello,

I'm sorry, maybe it was discussed previously, but I couldn't find references. I want to create a specific element representing a two-column block. Here is what I'm doing;

`
blockTools.insertAdjacentHTML("afterbegin", "

", contentType: "application/vnd.trix.columns.html" })`

The div is added, but whenever I'm trying to put any content in it, the text immediately disappears.

I see in docs that Attachments `can be moved or removed, but *not edited directly*`, but maybe there is a simple tool for wrapping blocks of text into divs with classes?

Start by reproducing the custom Trix.Attachment with contentType application/vnd.trix.columns.html and its contenteditable div. Read the attachment editing documentation and trace how content is handled when inserted into the attachment. Done would be a confirmed supported approach or a documented limitation with guidance for representing two-column content.

Written by the indexing model from the issue text.