$ elan install leanprover/lean4:stable
info: syncing channel updates for 'stable'
info: latest update on stable, lean version v4.0.0-m5
info: downloading component 'lean'
error: binary package was not provided for 'linux'
since this elan was installed as a debian package, it cannot self update:
$ elan self update
error: self-update is disabled for this build of elan
error: you should probably use your system package manager to update elan
since this elan was installed as a debian package, it cannot self update: