You're seeing this because Beta 8.x have made breaking changes that automatically makes any extension not updated since Beta 7.x not work.
Our extension guidelines give developers 1 month after a release as a grace period, and then we mark the extension abandoned here so that users are not confused or continue to ask for support for extensions that won't work with their current Flarum version.
This status is only marked here, it does not affect the state of the extension itself which may continue to be worked on by its developer, and any updated extension will have its abandoned tag reverted once it is again compatible with the latest version of Flarum. Alternatively, other developers can submit a PR on the extension's repository, or fork an extension with a permissive license (most so far have been released with such, notable exceptions being the recent Paid extensions) and do the work to update it to the latest version, and then release it on their own.
If you are still on Beta 7.x you may continue to experience these extensions working until you decide to upgrade to Beta 8.x. We try to keep an accurate reflection of compatibility state here with the latest Flarum version, although this tool from Flagrow can help you find extensions for multiple Flarum versions.
