To develop a large extension consider using webext-redux[0] and react-extension-boilerplate [1]
[0] https://github.com/tshaddix/webext-redux
[1]https://github.com/kryptokinght/react-extension-boilerplate.
[0] https://github.com/tshaddix/webext-redux
[1]https://github.com/kryptokinght/react-extension-boilerplate.
One use case is to create a single page app feel on websites that aren't single page. We use it in Salesforce, specifically.