Is it possible to make Firefox open a URL in a popup window?

I would like Firefox (the new super fast Quantum with low memory usage) to open some URLs in a special/popup window, i.e. almost without anything (toolbar, menu bar, tab bar, address bar, etc.) other than the web content. At the moment I can only do something like this by clicking a link in an HTML file with the following code: WhatsApp I wish I could do this by simply entering a command from terminal - or a standalone shell script would also do (ideally without the address bar, and positioned to the right and not left ;-) Any suggestions or ideas please?