There have been many posts regarding ssl certificates and auto acceptance and so on, one by myself i believe that was a little lengthy. However this suggestion is much simpler.
/server flag -e#, where # represents how the ssl certificate authentication is treated.
-e without a number would act normally.
-e0 would force the prompt to be displayed even if it was previously set saved and set to autoaccept (via the dialog prompt), and of corse subsequently overwriting/resaving that specific certificate.
-e1 would force the prompt to be hidden/not displayed, and auto-accept the certificate and connection without user interaction.
Whichever option chosen, the rule should apply to any and all subsequent automatic and manual (clicking the con/discon icon) reconnections within that server window/cid, unless a new /server command is issued to it.
I think this would make many users happy who leave mirc running while away from the pc and come back to find a server failed to reconnect due to failed ssl authentication.
More specifically, this is caused by either a new/unknown certificate (network leaf that hasnt been used before) or by a certificate that fails to save (and match the next time) correctly.