I filed a bug today about PDFs, Mail, and Messages:

Text copied from PDFs attached to mail messages cannot be pasted into Messages (both SMS and iMessage).

1. Open Mail.
2. Download & open PDF attached to email.
3. Select & copy text from PDF.
4. Try to paste text into new or existing Message (iMessage or SMS) — no paste prompt after tapping the text field.

After tapping the text field, a “paste” popup should appear.

Nothing happens after tapping the empty text field.

If you’re reading this and know someone who could push this forward, I’d be very grateful.