Hoople - 3:21 am on Dec 18, 2012 (gmt 0)
You have 3 blank lines in the start of your file before the DOCTYPE. It's giving the [validator.w3.org ] some issues as well as reporting more than a few errors. Ditto for the CSS validator [jigsaw.w3.org ] is reporting more than a few errors.
On Lubuntu 12.10 with Firefox 17.0.1 there is no discrenable difference when flipping from http to https tab. What OS and browser combination were you using? (So I and others can try to reproduce).
Welcome to WebmasterWorld jp12, next time post an extract of your code (per the forum charter linked above).