quick side-by-side windows

Windows 11 has a quick way to have side by side windows. For example, suppose I want Firefox in exactly half the display on the left and Excel in exactly half the display on the right. There seems to be support for quickly doing this in Windows 11. How can I do this in Ubuntu?

• Select the first window (e.g. FireFox) and press Super+←.
• Select the second window (e.g. LibreOffice Calc) and press Super+→.

The Super key is sometimes called the ⊞ Windows key.

For more details see Keyboard Navigation in Official Ubuntu Documentation web site.

As well as the keyboard shortcuts in the other answer, you can drag the top bar to the side to achieve what you want.

Ensure the window isn’t maximised (either click the double-square icon at the top right between the - and the X, or double-click the top bar of the window). Then drag the window to the far left or far right of the screen and it’ll occupy that half (you need to drag it all the way over). If you drag up it’ll maximise the window.

One of the nice features is you can have two windows with disproportionate split: drag one to the left and one to the right, then move your mouse to the split and the pointer changes to double arrows <> - you can then drag the split to the proportion you want. I find that useful when writing emails with source material in a webpage for example - I only need a small windows to compose the email and want to near-maximise the source.

The dragging of the split to change the proportions works if you use keyboard shortcuts or the drag method I’ve described.