So don't use a 3PID to add someone, use their MXID. It's a unique, global identifier and is similar enough to an email address. There's also a Matrix URI speci

So don't use a 3PID to add someone, use their MXID. It's a unique, global identifier and is similar enough to an email address. There's also a Matrix URI specification in the works (https://github.com/matrix-org/matrix-doc/pull/2312 https://github.com/matrix-org/matrix-doc/pull/2312). Once that lands, we should start seeing support for Matrix URIs in applications. This will allow applications to also start recognising MXIDs and converting them into working links, which will in turn help with people's recognition of the MXID.