Validation When You Save Code Changes
Validation failures are treated as errors and block changes
from being saved. Error messages explain the failures. Depending on the tool you’re using,
these errors are presented in different ways. For example, the Developer Console shows an
alert for the first error it encounters (1), and lists all of the validation errors discovered
in the Problems tab (2).
Validations are applied only to components set to API version 41.0 and later. If the validation service prevents you from saving important changes, set the component version to API 40.0 or earlier to disable validations temporarily. When you’ve corrected the coding errors, return your component to API 41.0 or later to save it with passing validations.