You may stumble on this process by accident but if you do, it’s unlikely you’ll know what you did and how to do it again when you need it.
If you need to make a web page bigger, do this:
From a Windows or Linux machine, hold the Control key and hit the + key. You may—or may not—need to add the shift key; I’ve seen both ways work. From a Mac, hold the Command key and hit the + key. You won’t need the shift key on a Mac. this will zoom into the whole page, and you may see a scroll bar show up on the bottom of the page. To zoom back out, just hold the Control or Command key and add the – key.
When you make this change, it works across the whole web site, but only for that website. When you move to another site, the new site is at its default size.
Hope you found this helpful. Let me know what else you want to know.