I have been running into a weird problem.
I am using metafields to show related products to the current product. My code works perfectly fine on one product's page but throws the above mentioned error on another product page.
For reference here's my code for this recommendations snippet where I am getting the "Shopify.formatmoney is not a function" error -
Thanks in advance!
Don't know if this will work for you but somehow I came across this solution while solving the same problem. No idea why but upgrading my jQuery version fixed this and a couple other problems for me. I was on an ancient 1.11.0, tried to go full upgrade to 3.2.1 which broke some more things, and finally settled on 2.2.1.
Again, no idea why this fixed this problem and a few other errors messages that have been plaguing my console for some time but it did. Presumably it has to do with other apps and plugins downloaded expecting recent versions of jQuery and rightly so. Please respond if this works for you too so others can see