Sound, Haptic, and Interactor Events dropdown doesn't expand on clicking its title under XR Ray and XR Director Interactor component in the Inspector, refer attached video.

Steps to repro:
1. Create a new project
2. Edit > Project Settings > Package Manager > Enable Preview Package
3. Window > Package Manager > XR Interaction Tool > Install
4. Hierarchy > Create > XR > Ray Interactor OR Direct Interactor
5. Ray Interactor > Inspector > XR Ray Interactor > Sound, Haptic, and Interctor Events

Actual Result:
Sound, Haptic, and Interactor Events dropdown doesn't expand on clicking its title

Expected Result:
Sound, Haptic, and Interactor Events dropdown expand on clicking its title

Note: XR Interaction Tool is introduced in 2019.3.0a1 with package version 0.0.6-preview

Reproducible in:
2020.2.0a16, 2020.2.0a5, 2020.1.0b14, 2020.1.0b6 with package version 0.9.4-preview, 0.9.2-preview, 0.0.6-preview

Working Fine in:
2020.2.0a4, 2020.1.0b5, 2019.3.15f1 with package version 0.9.1-preview, 0.9.2-preview, 0.0.6-preview

Environment:
Occurring on Windows 10 & Mac 10.15.

Workaround: On clicking dropdown icon its get expand