Plugins are disabled because an error has occurred. error="unable to set up plugins environment: unable to install plugin badger: unable to check archive integrity of the plugin github.com/fosrl/badger: plugin integrity check failed"
For v1.5.0, the SHA256 matched and /public/validate returned 200
For v1.6.0 and v1.6.1, the SHA256 from plugins.traefik.io did not match proxy.golang.org, even though the extracted contents looked the same
At one point /public/validate for v1.6.1 returned 404; later we also saw cached 200 responses that didn't seem to depend on X-Plugin-Hash, which made things a bit confusing to reproduce
Our best guess is that something on the catalog/validate side is unhappy with the 1.6.x archives (hash mismatch or stale cache), but we're not sure. We also wondered whether a retag of v1.6.0 could be involved, so we published v1.6.1 as a fresh tag, and that failed the same way.
If Traefik is throwing the error, I would open an issue there. Reference other. The devs usually check traefik/traefik. Make sure to stress that it worked in old versions, fails on new.
Not sure what picus is, never heard of it, project description could be more telling, probably to find GitHub plugins for Traefik and list them in the directory.