Crash adding a 0-size string to a MV_UNICODE prop

[jengelh]

Version: 23.0.23089.01 x64

Reproducer:

Select some folder or some message. Use Property > Advanced > Edit specific property. Pick property number: 0x1101f. (The MV editor comes up.) Add a value, but make it the empty string. Close the MV editor with OK. (The program crashes.)