product price does contain HTML entities like € 18,00€ 20,00(NaN%) OFF

[pimftw]

When I clone a fresh copy of this repo and install the added plguins it results in the product price containing HTML special characters.

[PaulCordo]

Yes might be due to this update from wp-graphql-woocommerce wp-graphql/wp-graphql-woocommerce#75
You now need to add a filter next to price values in your request like price(format: RAW)