I sometimes happen to re-watch some random episodes from shows I already fully watched with my roommates, and don’t intend to watch the whole series again,but those shows are now shown again in the watch next tab, and I would like to find a way to deactivate this, if it’s not already possible,that is. 
Thanks, but not sure I want to add yet another option just for this. Once you watch a newer episode it should work as expected. Otherwise maybe hide these shows?