If a project is already downloaded and installed, there is a "already enabled" indicator in the place of the "add to installation queue" link:

How about we turned this to a link to the project config page (if the project has one)?
- for already installed layouts, this link could be static, pointing to
/admin/structure/layouts/settings. - for already installed themes, we should be linking to
/appearance/settings/%theme_name%(if the theme has settings). - for already installed modules, we should be linking to whatever is in the
configure =entry in their .info files.
If the theme/module/layout is downloaded but not enabled, then show an 'enable' link that points to the respective project type manage page.
~~PR by @klonos: https://github.com/backdrop/backdrop/pull/1647~~ PR by @klonos: https://github.com/backdrop/backdrop/pull/2797
Recent comments
Thank you, this is a very useful workaround for preparing a clean import list. One concern remains, however: if Simplenews 1.x-1.2.3 still treats blocked user accounts as invalid...
Re-enable Simplenews newsletter subscriptions that had been erroneously disabled
@Amilenkov, I have an idea for your use case where you want to avoid re-subscribing people who have explicitly opted out: Build a view of simplenews subscriptions, and filter by Status (...
Re-enable Simplenews newsletter subscriptions that had been erroneously disabled
"modules to help someone monetise their own website"
How to monetize a Backdrop site