Applicable to Lightroom desktop (version 2.4) and Lightroom for mobile (version 4.4)
To support forthcoming improvements in sharing and collaboration, beginning with the August 2019 release of Lightroom, the ability to use flag and star ratings to hide photos in shared albums has been removed.
To honor the privacy of your hidden photos, all the visible photos in these albums will be placed into a new shared album that has the same URL, members, and settings as the original album, and the original album will be unshared.
You can find the new shared albums in the Photos folder under Shared to Web option in the Share tab.
To filter images in an album for sharing, do one of the following: