Choose custom email template for Contact Form plugin I could've sworn I've read somewhere on here that the contact form plugin should use the same template as defined in the site's email settings, but it's not working for me.

Does anyone know if the Contact Form plugin supports this (and has it working)?
The first part of the answer in the post you linked to is wrong in the context of the Contact Form plugin. 

Craft only takes the custom "HTML Template Path" email setting into account when EmailService's sendEmailByKey is called, which is used for pre-defined Craft emails.

The Contact Form uses EmailService's sendEmail, which won't take it into account.

It hasn't been released as part of an official Contact Form plugin release yet so there's no documentation, but thanks to this pull request, you've got an onBeforeMessageCompile event that will give a plugin a chance to modify the contents of the email.