Security question…another issue!!!

Just had a customer contact me with issues using the “Contact” form for a listing.
User states that they do not get a visual “equation” showing up in their browser.
“What is the sum of:” doesn’t make sense because there’s nothing to sum up!
She is on a Windows 8 machine. I did a check using browserling.com and, yup, sure enough it’s not there!!
WTH???