max-width-extension — Anon

If you are annoyed by web pages spanning the whole width of ultrawide monitors, like I am, this extension may help you.

For example, Google shows their search results on the left of the screen. Many other web pages show their content in the middle of the screen. Having to move my head back and forth all the time is annoying to me, so this extension should keep the content of web pages in the middle of the screen.