Search Folder or Conditional Formatting for internal company emails

I’m looking for a way to more easily recognize internal mail, i.e. mail coming from our @company.com domain.

I’ve been successful to do this for several external domains via Conditional Formatting (as described in Highlight mail from a specific domain) but when I try this for our own domain, it doesn’t work.

Is there a way to achieve this either via Conditional Formatting or a Search Folder for our internal mail as well?