If your email is still too wide and your Google Chrome and Microsoft Edge do not show a magnifier icon to resize Gmail to fit the screen. Then you can resize Gmail with the help of developer tools.

While in DeX, go to Settings > Advanced features > Labs > Multi window for all apps, then toggle it on. Now, every app will ...

A handy tool for presentations, demos and even accessibility, ZoomIt lets you zoom in on the screen, mark up the current page, and even capture your screen activity.