[ Install to Selected Site(s) ] - select only one site instead of 56 sites that are in the search

[riccardodicurti]

Describe the bug
In order to update a premium theme in several projects I navigated to "wp-admin/admin.php?page=ThemesManage" and searched for the theme, the results were 56, I selected them all and clicked Install to Selected Site(s), on the next page only one of the 56 sites was selected.

I have tried both "Show Themes by Item" and "Show Themes by Site".

To Reproduce
Steps to reproduce the behavior:

1. Go to "wp-admin/admin.php?page=ThemesManage"
2. Search for a theme installed on several sites
3. Click on " Install to Selected Site(s)"
4. See error

Expected behavior
That all 56 previously selected sites are still selected

Screenshots

Desktop (please complete the following information):

• OS: MacOS
• Browser Chrome
• Version 123.0.6312.87 (Official Build) (arm64)

Additional context
No additiona context about the problem