Mobile checker on the listing page and also the mobile friendly test
page. Both. However I finally switched to Chrome and the listing page
mobile checker worked there.
I use vintage buttons when I make primitive dolls for the eyes and
clothes so I always looking at yard sales and auctions. I found this
site for testing information. I use the hot water and the 409 test. If I
bought buttons, jewelry, flatware etc. on...
I found a web site that recommends 409 not simichrome or hot testing. It
is a great read for those interested in the testing subject. I have been
using the hot water and 409 testing with good results.
http://www.plasticfantastic.com/testing.html