9e373b3828
Copying a Discord thread (or any rich-text selection with images) attached one or more blank thumbnails and dropped the message text entirely. Two causes. The clipboard's `text/html` was scraped for inline `<img src="data:…">` regardless of whether the copy carried its own text — and what Discord ships beside each image embed is a 32x5 blurhash placeholder, which is exactly the blank attachment. Then, because any image blob short-circuited the paste handler, the prose that came with it never reached the composer. Inline HTML images now only count for an image-only copy, and are ignored below a thumbnail-sized floor so spacers and trackers don't attach either. A mixed paste attaches its real images and still inserts its text. Also registers pasteAndMatchStyle in the Edit menu — Cmd+Shift+V had no menu entry, so the chord was never translated into an editor command anywhere in the app.