My evaluation is 5 if I can save the current window size.

January 2, 2018 Addendum:
Since it became possible to set the current window size at Ver 0.6.1, I changed it from star 4 to star 5.

Not so nice that the Hotkeys are fixed to Alt+x - because the same Hotkeys also switch between open tabs ...

simple and useful

Very nice & useful add-on! Thank you

I've created two window sizes that provide the best aspect ratio for my most used applications, a news paper and weather site. Everything worked as expected. It would be nice to have an edit feature. Currently the add-on can only Add and Remove. Looking forward to improvement(s) in this app.

Increased to 5 star since the app now gives "edit" capability. Also, there is a new feature that allows you to resize the window and select, name and save the current size. Nice feature! Thanks for the good work.

Potentially useful, but buggy. I was only able to add one size, 800x600. When I then tried adding 720x1280, the add-on wouldn't let me save the new size

This is exactly what I was looking for today. Perfect timing. Glad it doesn't require the window position parameter. Thank you for this useful extension.

Rather pointless without 'window position' property.

UPD. I see. Sure you have your reasons.