Copying setting on different valves doesn't work. It's says that the valve has taken into account the modification, it says it only waits for the dup to change the setting, but dups never come until you manually set the number again, for each valve.
Steps to Reproduce
Build two valve. Send liquid through those. set one to 1kg/s for example. Copy setting, paste one the other valve. Dups never come to change the new setting. Manually set this second one to 1kg/s, and the dup will come.
This issue has not been confirmed by a developer yet.