Wrong icon is set for some scripts representing a class with the CustomEditor attribute when unknown conditions are met

Reproduction steps:
1. Open the attached “Grasshopper” project
2. Delete the "Assets/Samples" folder
3. Open Package Manager and install the Splines package
4. Open "Assets/Components/Editor" and observe the icons of the scripts

Expected result: All icons look the same
Actual result: “FlipEditor” and “PointCheckEditor” scripts' icons differ from the rest

Reproduced in: 2023.1.0a5, 2023.1.0a10
Could not test in: 2021.3.10f1, 2022.1.16f1, 2022.2.0b8, 2023.1.0a4 (icon change for CustomEditor scripts is not featured)

Reproduced on: macOS 12.5 (Intel)
Not reproduced on: No other environment tested

Notes:
1. Issue goes away after deleting the Library folder
2. The proper icon is set when moving the scripts to other folders