”Multiple HelpURL attributes detected” warning appears when having a regular [HelpURL] attribute on a base class and another [HelpURL] attribute on its derived class if the attribute on the derived class is a custom attribute

How to reproduce:
1. Open the user’s attached “Bug - HelpURL Inheritance.zip” project
2. Open “SampleScene” Scene
3. In the Hierarchy window, select “NewBehaviourScript” GameObject
4. Observe the Console window

Expected result: no warnings
Actual result: “Multiple HelpURL attributes detected” warning appears

Reproducible with: 2021.3.34f1, 2022.3.17f1, 2023.2.4f1, 2023.3.0b1

Reproduced on: macOS 13.6.3 (Intel)
Not reproducible on: No other environment tested

Notes:

• reproducible if the attribute on the derived class is attribute instead
• not reproducible if having a class that inherits from HelpURLAttribute to automatically format its URL based on a given type name
• not reproducible if having a regular [HelpURL] attribute on a base class and another [HelpURL] attribute on its derived class