Before filing issues, please check the following points first:

• Please don't open issues for security issues. Instead, file a report at https://www.npmjs.com/advisories/report?package=handlebars
• Have a look at https://github.com/wycats/handlebars.js/blob/master/CONTRIBUTING.md
• Read the FAQ at https://github.com/wycats/handlebars.js/blob/master/FAQ.md
• Use the jsfiddle-template at https://jsfiddle.net/4nbwjaqz/4/ to reproduce problems or bugs

We are using the latest handlebars 4.7.3, but we noticed that one of the dependencies optimist is deprecated. There is a ticket to switch to yargs instead (#1179) and it was closed with the merged PR (#1180). However, the merged PR is not in 4.x release yet. Please fix this in 4.x release.