Can you try :
- Edit slightly the original picture (so it’s not recognized as an existing images by Discourse, though I’m not sure it is if you paste if from your clipboard),
- Go to safe mode, everything disabled
- Create a post
- Paste/upload the picture
- See if the preview or result is cropped?
This is the kind of case were everyone’s trying hard to pinpoint an issue and in the end we’ll all be “That was so obvious”, right?
