Activity feed: Text file preview

[martastain]

Story

A user adds a text file attachment to a comment. It could be plain text, code snippet, markdown text, JSON or similar.
Their colleague wants to quickly check it out, possibly copy the text or a part of it, but they need to download the file, open it in the desktop editor, and view it there while opening it in the browser directly (possibly with syntax hl for common formats like JSON or markdown) would be more comfortable.

Problems

Discord suffers from a similar issue - when you paste a large chunk of text, it allows you to download it, but not preview it, so it slowly pollutes your download folder and it is messy.

Proposal

We already use a code editor with syntax highlighting in settings.

import CodeEditor from '@uiw/react-textarea-code-editor'

We could utilize it to display text file previews in read-only preview popover similar we use for image previews. With an option to download the file if necessary. Preview should allow text selection to copy the content, so it is necessary to disallow click-to-close.