188.8.131.52 Beta, 1.17.10, 184.108.40.206 Beta, 1.17.2 Hotfix
This might be a duplicate since it's hard to search for strings like this on jira.
Anyway, when you successfully load a structure, the following messages are printed:
These are the wrong translation strings, the correct strings are
which are translated to
1. Save a structure
2. Use /structure load to load it
Hilariously, there is also a key for commands.structure.unloadedChunks which states "The feature to load a structure in an unloaded area hasn't been implemented yet," which is not true