Hey Mate.
Well the issue is on the checkout page the Java Console states google fonts are not being loaded over https. Console Error Below:
[blocked] The page at 'https://domain.com.au/checkout/' was loaded over HTTPS, but ran insecure content from 'http://fonts.googleapis.com/css?family=Open+Sans:400,800,300,700': this content should also be loaded over HTTPS.
So I shouldn’t be getting this insecure notice should I.. as the wf.src should be loading it via https know?