It seems the only way to whitelist domains in Adguard Home is to provide a url to a file with the list of domains? Is this the case?
@baz you can add a whitelist file (menu: filters - dns allowlists) like a blocklist file (menu: filters - dns blocklists). But you can also whitelist anything you want by yourself.
go to menu - filters - custom filtering rules
you can type there what you would like to allow e.g. like this:
@@|domain.com^$important
or block e.g like this:
||domain.com^$important
replace domain.com with the url you want.
see also some more info at the documentation here: https://kb.adguard.com/en/general/how-to-create-your-own-ad-filters (https://kb.adguard.com/en/general/how-to-create-your-own-ad-filters)