There is no limit on the registration of specification fields, which can generate timeouts in the catalog admin.

• Register a very large amount of fields (i.e. 1000+) into a single specification.
• Open the admin of this specification Or try to change a product that contains this specification
• Receive a 404 or 504 request's response

Prevent: Do not register too many values in a single specification. Fix: Deactivate the specification and register the values in several specifications, preferably distribute in different categories Tip: Don't concatenate specs, especially in the root category