pushing vars to templates

A link dump on populating a Google Apps html template, followed by the javascript solution (without Google Apps) which was finally used.

https://developers.google.com/apps-script/guides/html/templates#code.gs_5 

explanation of problem

Passing data to html service - Desktop Liberation (google.com)

 

apparently safe way to do it

google apps script - How to pass a parameter to html? - Stack Overflow

 

Apps Script parameters with script.google.run - Stack Overflow 

not clear from documentation that <? ?> exposes top level variables.

 

correct syntax uses json.stringify

 

Javascript solution instead of Google Apps web app - 
https://github.com/hn-88/program/blob/main/index.html