Show background color when sending "Direct" message

[shuuji3]

When sending a post with "Direct" visibility, I'm sometimes a bit worried that I'm sending a public post by mistake because the only indicator for "Direct" is the @ icon next to the publish button.

It would be nice to have the same background color as the posted message in the editor too, so I can be more confident that the message won't be a public one. Also, it matches the style of the post result in the same way as the bold text is bold in the editor (WYSIWYG).

[stackblitz]

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