For alien content injected into pages, one possible culprit would be an extension. You can view, disable, and often remove unwanted or unknown extensions on the Add-ons page. Either:

• Command+Shift+a (Windows: Ctrl+Shift+a)
• "3-bar" menu button (or Tools menu) > Add-ons
• type or paste about:addons in the address bar and press Enter/Return

In the left column of the Add-ons page, click Extensions.

Then cast a critical eye over the list on the right side. Any extensions Firefox installs for built-in features are hidden from this page, so everything listed here is your choice (and your responsibility) to manage. Anything suspicious or that you just do not remember installing or why? If in doubt, disable (or remove).

Any improvement?

ExpressDirections is in your Add-ons Manager. Check its settings or disable it.

Thanks!

I think this will work.

Why the erasure of the lower left page when printing, I wonder?

hhoffman1 said

Why the erasure of the lower left page when printing, I wonder?

How large is the gap? Does it make any difference if you remove (or move) the footer information that prints at the lower left? I'm not sure where you set that on Mac, it may be somewhere in the Print dialog.