Exchange messages with programs other than firefox

1. Is Firefox send still available?
2. How to send message from background script to content script Firefox?
3. Does Firefox have an RSS reader?

Is Firefox send still available?

You will no longer be able to upload or receive files. We'd like to thank all of you who tried Firefox Send. We started Firefox Send as a way for you to share files safely and easily from any browser. Unfortunately, some abusive users were beginning to use Firefox Send to ship malware and conduct phishing attacks.

How to send message from background script to content script Firefox?

If you are wanting to send a message from your background script to your content script you should be using tabs. sendMessage() (Chrome/Firefox). Alternately, you can use the connect() methods in runtime and tabs , which then provide you with a port (Chrome/Firefox).

Does Firefox have an RSS reader?

Firefox has removed support for RSS in versions 64+, including the useful preview feature.