Ok so, here is what I suggest. I have run into some problems using mustache along with Jinja in terms of the double curly braces used by both engines while working on Firefox Health Report. One can escape the mustache code from being processed by Jinja but then you loose the ability to i18n the text. I ended up inlining the templates but, will be integrating the following JS solution to overcome this challenge and leave the JS templates inside JS files.

https://github.com/fabi1cazenave/webL10n/

Perhaps for right now, and to get this new version of plugincheck out the door, I can inline the templates and then we can investigate the feasibility of including and using the above JS inside Bedrock or else, explore the option of hacing Jinja generate the JS templates.