Reproduction steps:

# Create a new project
# Open Window → Package Manager window
# Add a Scoped Registry by following the steps in this [link|https://confluence.unity3d.com/display/Cinecast/Package+Candidates+Registry]
# In the Package Manager search type “Timeline” and install the Timeline package
# Go to the Timeline package directory and copy the package folder to another directory
# In the copied package folder open the “package.json” file and the change “version” variable to a lower version i.e. “1.6.0”
# In the Package Manager window install a package from a disk and select the “package.json” file from the copied directory of the package
# In the Package Manager window select “My Registries”
# In the search field type “Timeline”

Expected result: The Timeline package can be updated from the scoped registry
Actual result: The Timeline package is not shown in the “My Registries” tab

Reproducible with: 2020.3.42f1, 2021.3.14f1, 2022.1.23f1, 2022.2.0f1, 2023.1.0a21

Reproducible on: macOS 13.0

Note: Timeline package still can be updated from the “In Project” tab