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.
9e373b3828