In the VASL module users have access to a Mark Moved preference under the general tab in Preferences.
This preference seems to have disappeared between 3.6.11 and 3.6.12.
The mark moved functionality continues to work . . . which is the problem. There is no longer the capacity to turn it off which some players like to do.
I have tested this with various combinations of VASL and VASSL from VASL6.6.2 to VASL6.6.6 and from VASSAL3.6.7 to VASSAL.3.6.14. In those tests, moving from 3.6.11 to 3.6.12 is what caused the difference.