[Bug] Map validated, not playable solo

[adamkooo2]

Thanks tcq for the bug report, and thanks everyone for the help!
The bug will be fixed in a future update.
For your information, the bug does not happen because the item is put on a slope block, but because it is put on a ghost block (which is normally impossible, but for some reasons sometimes it is allowed... and then the item may disappear in solo modes).

thank you, I found it too when I was testing snow