Sorry, not wrong but 'NOT RECOMMENDED'
If the IP is without port then the usual form of
abcd:1234::1 is allowed.
When there's a port, the brackets should be used:
[abcd:1234::1]:12345
https://datatracker.ietf.org/doc/html/rfc5952#section-6
I wanted to copy the IPv6:port and paste it to another client. Unsurprisingly it wants the square bracket form.
