I appreciate you say that the theme may not be compatible with all plugins, however I would consider there is a growing trend the decimal qty is becoming quite a thing based on the different types of ecommerce websites.
So we have gone through 3 different plugins with allow decimal qty so users can buy fabric by the 1.1 meter etc
However it’s clear now that the theme is the issue, it works ok with store front, is there not a possible fix on this?
The issue is weird, as in where we set the decimal to be 0.10 the theme makes it 0.100000000 and so on and so creates odd behaviour as you go up
