don't have the integration when installed from HACS.

[temmink]

I tried to install the prelease of icloud3 through HACS. I downloaded the repository, and I choose the version (I think it was mentioning 2.4.9).

after rebooting the raspberry (and so restarting homeassistant) I don't have the integration available, not even after cleaning my browser cache, just to be sure,

The files are loaded in the custom-folder of Homeassistant.

how can I enable icloud3, so that i can start configuring/using it?

[gcobb321]

Enable beta versions on HACS. Then you should see v3 rc9