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#12538 (moved) replaces most uses of DirPort_set with dir_server_mode, #4483 (moved) adds another use of DirPort_set.
I don't know what order they'll merge to master, if #12538 (moved) merges first, we'll need to replace the DirPort_set in #4483 (moved) with dir_server_mode.
(There might be commit conflicts due to these changes.)