Visit and clone the repo
https://github.com/opentok/screensharing-extensions/tree/master/firefox/ScreenSharing
****I already prepared for https://www.hemengorus.com ****
https://github.com/bahadirodevci/imonacloud-web/tree/master/HemenGorus%20ScreenSharing%20Firefox

Edit the contents of the install.rdf file. Be sure to change the id, name and version settings, and ensure that targetApplication:maxVersion -- Change this to the latest Firefox version listed on this page

Edit the bootstrap.js file. Set the gDomain property to match the domain(s) your screen-sharing extension supports. In this case, "*.hemengorus.com",

• Website must be https

Package the extension by creating a zip file that contains the install.rdf and bootstrap.js files, with the file extension changed from zip to xpi. You can run the following on the command line:

zip my-screensharing-extension.xpi install.rdf bootstrap.js

If you changed the old one and update the addon, **Dont Forget to upgrade version number in install.rdf **

<em:version>1.1</em:version>