HI, Firefox reported what it found. It is up to the site how they configure things. I would think that since it was not a address that had private submission of personal details that the page had mixed content or the page was on a less secure URL having mixed content.

Also the URL does not : This web site does not supply ownership information. Firefox would like to see that in a Certificate.

I did not get the error when viewing in Private Browsing. Sorry, I do not see a error in viewing nor what you have stated that it is a real bug.

Please let us know if this solved your issue or if need further assistance.

> I would think that ... the page had mixed content or the page was on a less secure URL having mixed content.

No, it is a single PDF file. (you said you tried it, didn't you?)

> I did not get the error when viewing in Private Browsing. So you got "Secure", but insist that if it says "Insecure" for the very same page that is not a problem?

Are you having this issue across other pages, if yes a problem. if no is a one off that we all possibly have better things to do than trouble shoot one page. You did get the PDF is that not correct ?

Not that do not want to help but I had no problem with the page. So very, very difficult to figure that sort of thing out. As mentioned if across other pages we will tear you apart to help you figure it out.