Allow text selection in Markdown Previewer

[coszio]

Currently, I don't find a way to select text directly in the markdown preview window. The only way to copy things is when there is a code block, which does show a Copy code block action.

Sometimes I am just reading a markdown, which is nicer to do in the previewer, and I don't want to go back to the source just to select text.

My feature request is to allow using the mouse to select text in the previewer... please? 👀

Regarding what it actually sends to the clipboard when copying, I don't have a particular choice; it can be just the text, or the underlying markdown.

[SomeoneToIgnore]

#16727