Where does the value for the font-family property come from in firefox?

Question

css

The method $('.foundation-mq').css('font-family')returns the wrong value of the given class, instead
"small=0em&medium=48em&large=64em&xlarge=75em"
returns

"serif, \"small=0em&medium=48em&large=64em&xlarge=75em\""

Because of this, the work of the plugins of the Foundation framework breaks.
The screenshot shows that the name of the point is smallincorrect.

The problem appears on the PC version of Firefox. If you look at the "Calculated" tab for this class, then there is just a value with serif, but I don't use it anywhere.

Where does serif come from and how to fix the problem?

Answer 1

Problem solved, there was a bug in firefox. Reinstalling helped.

Answer 2

if you yourself define it somewhere, then try adding the !important directive there and then try again in jquery to call the value. Will you get back what you want?