insert extra field – datetime – in profile?

This plugin might work (if it supports the type: datetime, I’m not sure)

https://www.ads-software.com/extend/plugins/custom-field-template/

There isn`t support of datetime , only textarea

you could try asking the author of that plugin, to add a datetime field feature! Maybe he can do it

Hiroaki has posted on this forum recently
https://www.ads-software.com/support/profile/471527