I just switched to Firefox and struggled with this exact functionality. The posted site ships a script for curl|sh that creates a new firefox profile with a cus

I just switched to Firefox and struggled with this exact functionality. The posted site ships a script for curl|sh that creates a new firefox profile with a custom userChrome.css. There is an official thread here with people discussing how the single-page-as-an-app functionality should work: https://connect.mozilla.org/t5/discussions/how-can-firefox-create-the-best-support-for-web-apps-on-the/m-p/71778 https://connect.mozilla.org/t5/discussions/how-can-firefox-c... I ended up writing a firefox extension to open up URLs in a new "popup" window[1]: https://addons.mozilla.org/en-US/firefox/addon/web-app-maker/ https://addons.mozilla.org/en-US/firefox/addon/web-app-maker.... I just checked it on Windows (usually using linux) and the popup window type does not allow the maximize button to work. Oh well... [1]https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/API/windows/create#type https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/Web...