Since we've introduced the image renderers, customers who attempt to paste an Excel file see a "data:image/png" text instead of the pasted data.
Excel is too clever. The clipboard data contains text/plain, text/html but also an image of the table as "image/png". It's nice in case the recipient doesn't allow text !
You might think 'Ok, why don't you just take the first receivable item?' Well, here's what happens when pasting a image file:
We'll just check, if there's some text/html, we'll treat it as a table; if there's image/png, we'll treat it as an image, otherwise as text.