Smart HTTPSby ilGur

Note: Smart HTTPS (revived) is a revised version of Smart HTTPS addon and, is written with the new WebExtensions API. This new version has better performance and robustness comparing to the old Smart HTTPS which was written with addon-sdk API. If you have Firefox (version 51 and above), please consider using this addon.

Smart HTTPS is a Firefox addon that helps you always use the secure HTTPS protocol, if supported by the server. It automatically changes HTTP protocol to the secure HTTPS, and if loading encounters error, reverts it back to the HTTP protocol.

HTTP vs. HTTPS:
HTTP, or Hyper-Text Transfer Protocol, is the way a server communicates with the browser. HTTP enables visitors to view a website and send information back and forth to the server. HTTPS, or Hyper-Text Transfer Protocol Secure, is communication through a secured connection. Communications through an HTTPS with the server are encrypted by a secure certificate known as an SSL. The encryption prevents third-parties from eavesdropping on all communications to and from the server. Read more about HTTPS at the Addon's Homepage.

Some Key Features:
a. Seamlessly changes all HTTP requests to the secure HTTPS, and if an error occurs, reverts it back to the HTTP address (and remembers this choice).
b. All websites (addresses) that do not support HTTPS, are saved to memory in order to speedup the protocol-check process. Note that you can see and delete these items from the Addon's Options page.
c. Toolbar button serves as the ON-OFF switch to turn the extension ON or OFF. Blue color indicates ON state and Gray color is for OFF state.
d. (v0.1.2) You can now add desired websites to the white-list manually (see Addon's options page).

A Sample Scenario (based on a question from a user):
When you install the Addon for the first time, you will visit its support page. Since this page does not support HTTPS protocol; the Addon first loads the address in HTTPS, and when it sees the error (it this case the error is the Firefox’s certificate-error page) reverts the address back to HTTP. But this operation is so fast that you will not see the error page at all. However, it is available in the browser’s log (or history) if you check. In simple words, SMART HTTPS’s procedure is as following:

For any HTTP address, loads the page in HTTPS >>> watch for any sort or ERROR page (such as cert-error, blank-page, not-found-page, etc.) >>> reverts the page back to HTTP

Furthermore, SMART HTTPS only monitors HTTP websites and does not have any effect on HTTPS addresses at all. The behavior of SMART HTTPS is very similar to what human does to check for HTTPS protocol. You first change an HTTP address to HTTPS and if you see any errors happening, you will change the address back to HTTP. This is exactly what SMART HTTPS does, but in a much faster manner. This Addon is also available for Google Chrome and Opera browsers and has exactly the same behavior in three browsers.

Note: in order to report Bugs, please visit Addon's Homepage and fill the Bug report form.