Reproduction steps:
1. Open the attached “Repro.zip” project
2. Open the “Assets/Test.inputactions” Input Action Asset
3. Select the “Delta [Mouse]” Action under Test
4. Click the “+” icon near the “Processors” in the Binding Properties
5. Observe the available options
6. Enter/Exit the Play Mode
7. Repeat steps 4 and 5

Expected result: “Delta Time Scale” option is available
Actual result: “Delta Time Scale” is missing

Reproducible with: 1.3.0, 1.4.4, 1.5.0 (2020.3.46f1, 2021.3.21f1, 2022.2.12f1, 2023.1.0b9, 2023.2.0a7)

Reproducible on: Windows 10 Pro (22H2)

Note: “Delta Time Scale” option becomes available again after Unity Editor restart