Does the bar indicate its source? I suspect that it is generated by an extension, which you may or may not have installed intentionally.

Please check the following tab and disable anything nonessential or unrecognized, then restart and see whether the bar is gone:

Tools > Add-ons > Extensions category

(Windows users, you may find it under:
orange Firefox button > Add-ons > Extensions category)

Any luck?

If none of the extensions seem relevant, could you post a screen shot of the bar?

The bar is still present when all of the extensions are disabled. There isn't much to see as there isn't anything that actually shows up in the News bar. (Note: First pic is with news, second is without news.) It just leaves a bit over half a centimeter of empty space between the bookmarks and the navigation bar.

This isn't anything critical, just vaguely annoying. Getting it disabled in a window is just right clicking and unchecking "News".

Hmmm, in that case let's try Customize.

View > Toolbars > Customize
or
right-click > Customize

Drag all items off of the News toolbar back to the Customize dialog so it is completely empty from end to end. When you click Done, Firefox should delete the bar.

Does that work?

I have no idea how, but it did. The only thing that was there was a little spinning loading wheel, and that disappeared on its own. Thank you for your help. Also, if there wasn't anything there, why would the loading wheel have been attached?

Some questions cannot be answered definitively... The file that stores toolbar customizations gets modified by many different processes, so it can get corrupted occasionally, and this may have been one of those cases.