Migrate our Schleuder lists outside of boum.org

Originally created by @intrigeri on #16121 (Redmine)

Subtasks

• #16217 (closed)
• #16218 (closed)
• #16251 (closed)
• #16252 (closed)
• tails#16254 (closed)
• #16256 (closed)

Related issues

• Related to #16255 (closed)
• Related to #16767 (closed)