What is the recommended maximum size for a Sidekiq job payload?
See this article, you should make your job parameters small and simple. Just store some simple identifiers, and then Look up the objects once you actually need them in your perform method.
And Because it need serialization and deserialization, it will be extra cost to you add the html content to job. So just save the html-content into string or some container and send the string id or container id to redis for efficiency and simplity.