Hi, there are too many ways to check each one individually so some assumptions had to be made, for example that level=0 is redundant. In the majority of cases level is mistaken for layer and used in combination with bridge/tunnel=*. In some cases the bridge was removed, but the layer/level tags not. There were also forest tracks marked with level=0, which is baffling.

I will take a look which of the removed tags make sense to be reverted.