IMAP: Request server capabilities
IMAP servers have many optional functions, whcih can be supported or not supported by the particular server or even be not available to particular clients.
IMAP servers provide the list of supported capabilities (functions) as a list. The format of the capability list is defined in the RFC. TElIMAPClient class will pass the list via OnCapability event. Alternatively you can get the full list via Capabilities property.
Depending on the value of AutoCAPA property capabilities are requested automatically after connection and/or after login. Note that the lists of capabilities can differ before and after login.
TElIMAPClient automatically takes care about advertised capabilities that might affect the client's behavior (eg. the list of supported SASL authentication mechanisms).