Two clipboard representations
Copy for Gmail or Outlook writes safe semantic HTML and plain text when the browser supports rich clipboard writes. The email composer chooses the representation it accepts.
The HTML contains headings, paragraphs, emphasis, lists, links, quotes, code and simple tables without source font, colour, background or class attributes. The plain fallback writes link destinations explicitly.
Gmail
Use the formatted copy in Gmail's normal rich-text composer. If Plain text mode is enabled, use Copy plain text because rich styling cannot survive in that mode.
Pasteful does not access Gmail, address the message, insert a signature or send anything.
Outlook
Outlook exposes client-specific paste choices. Clean rich copy is the starting point. Merge Formatting can be useful when the draft should adopt an existing corporate template style.
Classic Outlook, new Outlook, Outlook on the web and Outlook for Mac can differ. Check a list, a link and paragraph spacing in the client you will send from.
Current boundary
This destination formats a newly composed message body. It does not yet parse a copied email thread, remove quoted replies or detect signatures. Those source-cleanup features require separate fixtures and an explicit preview because the removed content may be meaningful.
Paste it into Pasteful. It stays in this tab.