I use an ultrwide monitor so I often view two webpages side by side, now for exmaple if I snap firefox to the right side of my screen it works fine, but I can't then drag out a tab and snap it to the left side of my screen and maximise the space in one go, in Windows 7 this used to work.

In windows 10 you have to drag out the tab, then drag and snap to maximise the space fully, in chrome for example it works in one go, just drag the tab and snap, maximise in one go.