4.2. Client-side usage
When used client-side, the file defines aliases that the client can use as alternative connection strings, and the configuration the client uses for the connection if the connection string matches that alias, or the value of that alias, exactly.
The value of the alias can only be a filename, or a legacy connection string. At this time, modern URL connection strings are not supported. See also firebird#8302.
Only per-database and client-side configuration items are supported, other configurations items are ignored.
It is possible some connection properties are only per-database server-side, and global client-side, or vice versa. If you find such a case, please report it on the firebird-documentation repository so we can update the documentation.