Width of opening page too large

I have a small but frustrating problem.

Whenever I open a new page, it is about 1 inch too wide. To observe it
completely, I have to keep shifting back and forth, from left to right.

I am sure the answer is obvious and simple, but I can't figure it out.

I'd appreciate any help.

George Sweeney

Drag the little corner from the bottom right out if you haven't already tried pressing the "green" + size button on the top left corner.

It should "automatically" size it and if it doesn't the first time, it does normally two clicks after that (first one being to make it smaller and then the second to make it bigger again).

-rockstate

You may be accidentally zoomed in on the page. Hold down the Control key and use the mouse scroll wheel to zoom. Make sure you're zoomed all the way out.