The same paragraph had two sentences mentioning Mr. Dixon, so Emma certainly had him on her mind.

Emma decided not to dislike Jane as a consequence of her "twofold complacency" (pleasure and rendering justice). Rendering justice is punishing the guilty and protecting the innocent. How does Emma liking Jane protect her?

A few sentences later, Emma reverted to her dislike of Jane (These were charming feelings, but not lasting.) Is Emma's justice more ephemeral than a Mayfly? If Emma really wanted to render justice to Jane, she should stop thinking about a romantic connection to Mr. Dixon and she certainly should not mention her theory to Frank Churchill!