Only supports width and the "viewport" options don't resize the viewport, they resize the actual window making them redundant.

Only supports screen width, but not height.

Hey could you please add keyboard shortcuts and not change the window size when I change the viewport? That would be great, thank you

Has bugs and seems to be an Alpha Test version. Maybe sometime in the future. Deleted.

This only resizes the viewport or window WIDTH, which are both equal. What good is that? I need to resize the viewport HEIGHT.

This does exactly what it says and does it snappy and well. They execute their promise to perfection, so I give it five stars! I would love to have more width options, or the ability to add more, but those would be great features to add and do not reflect the delivery of what this extension promises. There is room to improve it, but

Only adjusts window width - looking to adjust height as well

Just not worth the time. It DOES NOT 'STICK'. Sites reloading just push back to the stupid full screen. What about the LENGTH of the window?? Disappointed.

Working fine with no problems. The responsive mode (ctrl+shift+m) with draggable screen dimensions is very useful for checking all breakpoints.

Excelente

Useless, customization unable and small width.

not customizeable, ctrl+shift+m is useless for my use case (and if i was going to use built-in features i wouldnt be looking for add-ons)

Great add-on, and the Ctrl+Shift+M mode really makes it shine (you should add this mode in the little graphical UI, given the amount of people that miss it)
Not given 6 stars because for really large sizes, it is a little buggy (selection areas go far right instead of centered above screen)
Really good job anyway

Not usable on Mac OS, the shortcuts CTRL-Shift-M or CMD-Shift-M don't work.

Feature-Request: analyse CSS media queries in the currently open page and show them as options to select.

Thanks!

Very simple, just like how i want it. BUT, you really need more sizes above 1280. And have the option to customize. Has lots of potential though.