I noticed that we have two tags that appear to be very closely related: crewed-spaceflight (171 questions) and crewed-missions (23 questions). The question overlap between them is minimal; only four questions are tagged with both.
The tag wiki don't really provide any guidance on the difference between the two. crewed-spaceflight:
Crewed spaceflight (also referred to as human spaceflight or manned spaceflight) is space travel with a crew aboard the spacecraft. When a spacecraft is crewed, it can be operated directly, as opposed to being remotely operated or autonomous.
and crewed-missions:
Use this tag for questions relating to missions that are manned by a crew.
What's the difference between the two? Which should I use when? Or should they be merged?