When you serve the webmail on multiple hostnames, each hostname can override a subset of branding fields. Unset fields fall back to the global values. Match is on the request's Host (or X-Forwarded-Host) header.
Use "." to match any subdomain (e.g. ".example.com" matches mail.example.com and any deeper subdomain, but NOT example.com). Exact matches always win over wildcards; the longest wildcard suffix wins among multiple wildcard matches.
Declarations
Type
attribute set of (open submodule of (JSON value))Default
{ }