I am not sure why this

It would be nice to be able to specify the intermediate certificate (bundle) separate from the certificate, so when updating the certificate I just have to replace this file.

Something like

local_name mail.xxxxxx.xxx { ssl_key =

Or

local_name mail.xxxxxx.xxx { ssl_key =

dovecot-2.2.36-3.el7_7.1.x86_64