Firefox has a button on the toolbar to show your current session downloads, but the button is hidden until you have downloaded the first file.

If you are looking at an article and it doesn't offer its own download or save button, I think your built-in options are:

• Print -- you can use the "Save to PDF" printer as your Destination
• Save Page As -- this saves the page as HTML and optionally includes the images and other related files

There also are some add-ons that can save the page with all the bits and pieces included in one file, which may be more reliable than the separate bits and pieces method. For example:

https://addons.mozilla.org/firefox/addon/single-file/

I should add:

If you are reading a PDF in Firefox's built-in PDF viewer and you want to save that to your computer, there usually is a download arrow on the viewer's toolbar. However, some sites use their own PDF previewer that doesn't have the same buttons, so in that case, you may need to look for another method to save the file.

Are there any particular pages or sites where there's no apparent way to download?