gsd-housekeeping should skip mountpoints in /tmp
systemd-tmpfiles-clean in the beginning, so you can read the whole story here: https://github.com/systemd/systemd/issues/12692
Basically I quickly mounted a remote location to
/tmp/foo because I had no root rights to create a mountpoint in
/mnt. Then something deleted all files older than 14 days from the mount. As we excluded
systemd-tmpfiles-clean as a suspect, the culprit was probably
gsd-housekeeping and its "feature" which delete temporary files older than n days.
gsd-housekeeping should skip mountpoints or, in general, files and folders on other devices.
Edit: Fedora 27,