I also have the problem:
I use a couple of checkers https://sicher3.de/google-fonts-checker/ it seems after an hour it fails with these:
https://fonts.gstatic.com/s/roboto/v18/kfomcnqeu92fr1mu4mxk.woff2
https://fonts.gstatic.com/s/roboto/v18/kfolcnqeu92fr1mmeu9fbbc4.woff2
– i even downloaded those two fonts and put them in css but I don’t know what this v18 is a font size?
I think my revolution slider which had a youtube video had the problem which I removed the youtube video. Now I did a check and it did not fail, but yesterday I waited a few hours checked and it was back. I disabled two youtube plugins also hopefully I fixed it.
I think is a problem still because in my inspector I still show font’s see first image in link https://imgur.com/a/YH08r9E from fonts.googleapis.com and from fonts.gstatic.com
I want to be sure all font’s are local so I don’t know why inspector shows this or how to fix it?
The main font culprite was Roboto, which I downloaded every font and put in my css.
I tested 3 times while writing this and the checkers seem ok, but we have someone trying to get money from us because we served google font’s from the EU to USA. I have to be sure all is local now.
Please advise, thank you