No, there are multiple images on my own website that can reproduce the issue, but I haven’t done much investigation on Meta and have only found this one case so far.
No, in fact Discourse is smarter than we thought. For example:
A user on my website uploaded an image, and under the Markdown editor it appears like this:
...
...
I obtained its full link through the browser’s developer tools: https://example.com/uploads/default/original/1X/8826bc6c1be0e501979df4a004b9b2ae51c50320.jpeg . So I referenced the image in the editor using the full link format:
After dragging without clicking (triggering an upload) in the rich-text editor, the content in the Markdown editor becomes:
It can be seen that although Discourse shows that dragging triggers an upload, the image actually appears as  , which corresponds to the same attachment originally uploaded by that user as https://example.com/uploads/default/original/1X/8826bc6c1be0e501979df4a004b9b2ae51c50320.jpeg .
- Dragging an image referenced in the
format also results in the same handling.
From this perspective, triggering an upload again does not actually take up additional storage space — only the first uploaded file truly occupies server storage. So it’s just a user experience issue: users get confused about “why does dragging an image (when I click and then drag without releasing the mouse) fail to move as expected, but instead shows an ongoing upload and duplicates the image?”