It works, has settings to manage auto-opening in Web App Mode, and has a settings to control the size of the window plus the position. I have yet to find an issue with this.

Would be 5/5 if opened fullscreen

Não funciona. Não cria WebApps como o Edge ou o Chrome fazem.

Hey, thank you very much for this addon. It is perfect. I was also looking for how to match the window I am openning from command line (or windows taskbar) and luckily I've found solution to my problem. Posted here: https://github.com/ettoolong/WebAppMode/issues/1

Worked fine on last year. But not now.

Figured out how to get it to work, thank you for this! It's a concept that I desperately wanted in Firefox, but couldn't figure out how to implement it. The only thing that's a bother, as others pointed out, is the necessity to maximize the window manually, but I read your response to a review on the popup add on saying that this is an issue with Firefox itself.

Horrível. Não funciona

Loved the idea and execution, but https://web.whatsapp.com does not play well in "App Mode" (likely due to Whatsapp's own scripts that assumes there's always a title, menu and/or address bar, throwing mouse pointer navigation off vertically).