hmmm, noone knowing what the donation is used for?
then i guess its simply some extra benefit to the pool-creator without any certain intent?
Donation is a donation to the pool op - if you like the pool, the service and everything is like you want - donate a bit

another one: the suprnova-website (-> getting started) states that anonymous mining is possible by specifying a (ZEC-)address as username.
mining statistics should be further available through
https://zec.suprnova.cc/index.php?page=anondashboard&user=
i've tried to do so but all i get is a dashboard-page where all values are missing even if i have submitted multiple shares before (no balance, no workers listed, empty histograms,...).
the address used also has not yet received anything so i guess there is a payout-threshold? if yes, how high is that, if no, how does one trigger a payout for anonymously mined ZEC?
again, thanks for your help!
The payout threshold is 0.01 ZCL and you need to define a rigname when mining. So for example when you're mining with t1xxxxxxxxxx as wallet address, your username for the miner should be t1xxxxxxxxxxxx.rig1 or .rig2 etc.. Then you can access the statistics for that address using the Anondashboard link on the Homepage.