Problem: standard_commands::guid_context_file_properties and standard_commands::guid_context_file_open_directory are equal.
Status: Will be fixed in a future version.
Solution:
Invoke "Properties" and "Open directory" by name through menu_manager::run_command_context().

Suggestion for any workarounds reported or not, add #warning or other workspace/solution note for all workarounds so they are easily tracked and removed when they are no longer necessary.