Reproduction steps:
1. Open new Unity project
2. Attempt to drag and drop an external file into the Project window

Expected result: You are able to drag and drop an external file into the Project window
Actual result: You are not able to drag and drop an external file into the Project window

Reproducible with: 2022.1.0a13
Not reproducible with: 2019.4.32f1, 2020.3.21f1, 2021.1.27f1, 2021.2.0b17, 2022.1.0a12

Note:
Adding files to the project via windows explorer still works