I’m terribly sorry about releasing two versions in one day: I’ve released 7.4.1 in less than an hour after I became aware of the SSL problem, and apparently I forgot to update some parts of the code.
If you are running 7.4.1 and have SSL Security on, XKit will not work on the blog frames (the little buttons that appear on the top-right corner when you visit a blog), so extensions such as View on Dash will not work. XKit 7.4.2 fixes this bug.
And once again, in case you’ve missed, if you have the new “SSL Security” setting on on your account, and using 7.4.0 or below, you have to update your XKit or it won’t work at all on your account until you do. (The reason for this is explained here.)
If you don’t use SSL Security and don’t plan to turn it on, you don’t need to update your XKit yet.