Package Manager Window does not refresh the packages list under "All" after removing keyword from the search field under "My Assets" and also the "Load next (25) or (100)" button for "My Assets" does not work.
The only workaround is to close and reopen the Project.
Refer attached videos.

Steps to Reproduce:
1. Create a new project
2. Window > Package Manager > Packages > My Assets
3. Search for anything
4. Switch to All
5. Remove the search keyword (Observe Result 1)
6. Switch to My Assets
7. Refresh Packages
8. Load next 25 or 100 (Observe Result 2)

Actual Result:
1. The packages list does not refresh.
2. Load next button for 25 or 100 doesn't work

Expected Result:
1. Packages list refreshes after a moment.
2. The next 25 or 100 assets should load in alphabetical order

Occurring on:
2020.1.0a18, 2020.1.0a17

Working Fine on:
2020.1.0a16, 2019.3.0f4

Environment:
Windows 10 and macOS 10.14

License type: Free