Field instances require the name field to be unique, but don't enforce it which leads to errors

[viktor-yunenko]

Eg as a consequence fields with identical names are being merged into one field:

The following form submission:

• name = 1 value
• name = 2 value
• name = 3 value

Is going to be saved as:

• name = 3 value
• name = 3 value
• name = 3 value

[viktor-yunenko]

It might have been fixed on the release/6.0.x branch.