I have Facebook's plugin integrated and working just fine without this addon enabled (but get mixed content errors on IE). So, I use this addon, which magically cures that problem. But suddenly Facebook cannot scrape any pages, and its debugger spits out a redirect error.
Facebook gets redirected to HTTPS, as it should be, but completely fails to access anything via HTTPS. This is strange because it can scrape HTTPS just fine with the addon disabled.