Currently the support for templating is limited to a certain amount of cards. unfortunately there is no consensus, nor unified and consistent way which gives template inside cards a steep learning curve (if supported at all!).
Some card fields do support JINJA2, some card fields support JavaScript templating, but there isn’t a unified way, or is it obvious that templating on a certain field is supported at all. Even what templating engine isn’t clear from the UI.
My request is to choose 1 of the 2, and implement these on all cards and fields, so the usage is unified and consistent with optimal flexibility for all users (power users and beginners).
I lean to the support of JINJA2, as the support is native home assistant code, with plenty of examples in the fora.