In Adobe Acrobat, I have to move my mouse to the lower left-hand corner of the page to see the dimensions in a PDF file. Is there a way to turn this on permanently?

Yes! You can set both Adobe Acrobat DC and the free Adobe Reader application to always display the dimensions of the PDF when opened. To set Adobe Acrobat DC (or even the free Adobe Reader application) to always display the page size, go to Adobe Acrobat DC > Preferences > Page Display. Under the Page Content and Information section, check the box for Always show document page size.

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