to bundle the extension for submission to Chrome/Firefox store run in terminal:

• cd /to/root/of/extension
• install npm if you don't have it
• npm install (first time, or if any new npm packages have been added)
• npm run build
• ./create_release_zip.sh

This will output extension.zip, extension_unobfuscated.zip and extension.dev.zip to the extension_outputs folder. Upload extension.zip to the Chrome and Firefox stores. Firefox additionally requires that we upload extension_unobfuscated.zip so that they can review our unobfuscated code. extension.dev.zip includes a development build that can be used for local development.

To develop on Firefox:

• Hamburger -> Add-ons and Themes
• Gear icon -> Debug Add-ons
• Load temporary Add-on...