One thing that I quickly do on my browsers is turn off warnings about non-secure data when browsing secure pages (with HTTPS .)

It's rarely a problem and with all those features you like to have (Facebook, Twitter, AddThis, ShareThis, Google Plus, and othe fun widgets...) it's hard to avoid. Actually, many times the problem lies in one of these scripts and thus you cannot just fix your website. Without that 3^rd party script owner fixing their code, it just won't work at all.

Now, once in a while I work on a customer website and they really want to have a 100% clean slate. Thus, you need that flag to be turn on. So far, I've not founf it in the preferences. You have to go in the Firefox settings to revert the flag to the default.

URL: about:config

Click on the button saying you'll be careful, then in that very long list search for:

security.warn_viewing_mixed

and make sure it's set to true (if false, it should appear in bold.) If not true, right click on it and select Toggle to change it back to true.

That will again get Firefox to show SSL versus non-encrypted content warnings that were hidden because of that dialog...