Solutionunvalidated
As you can see in the source code for `Symfony\Component\Security\Http\RememberMe\RememberMeDetails::toString()` — your cookie is normal. Outcome: The string is composed of the user class FQCN with `\` replaced with `.`, followed by other parts and separated by a `:` which is encoded as `%3A`.
79d9f689-f1ba-4519-9f4a-8e368c01fc1e
As you can see in the source code for Symfony\Component\Security\Http\RememberMe\RememberMeDetails::toString() — your cookie is normal. Outcome: The string is composed of the user class FQCN with \ replaced with ., followed by other parts and separated by a : which is encoded as %3A.