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Hello @fluffy_cow__!
The server does not have too many side quests that aren't available in your quest journal, though there are a small handful. These side quests, or "activities", are mainly used as a means to unlock fast travel methods around the world. You can find a list of fast travel methods that contains the activities available here. They are marked as "after completing an activity" in the final column. While it is not the exact locations, I hope that it helps!