Bring-your-conversation-to-matrix link

[jtagcat]

User A is generating the link, must be an user.
User B is any other party, may be an user.

A generates an unique link, gives access to other platform's chat and specifies user on the other end and shares the link.
Future solution for popular email platforms (such as thunderbird, gmail) could include automatic link generation for each email and signature, though that would mean giving access to all your email. (add a move this email to chat link in the signature)

If party B opens the link, it will act as a matrix.to link. If registration goes well, it captures the newly registered username, sending a chat request from A and also pasting in the previous chat.

B needs to accept the chat request and effectively email or an another chat platform will not need to be revisited.

From Matrix side it would need access to accounts, to initiate a dm and to paste in the previous conversation. This will be from only side A. First time link generation may need a prompt, to give access. I'd note that it's currently not possible to have a dm with a bot in it, it will no longer be under 'people'.

This link would bring users in and solve the chatty email problem.