Incomplete oms.xsd solver schema

[GorbadPS3]

The schema specification does not mention VariableStepMaster:

https://github.com/OpenModelica/OMSimulator/blob/master/schema/oms.xsd

OMSimulator seems to support VariableStepMaster, VariableStepSolver and FixedStepMaster solvers, but the schema oms.xsd does not mention VariableStepMaster.

Is VariableStepMaster missing on purpose, or is it a mistake?

[GorbadPS3]

NOTE: https://github.com/OpenModelica/OMSimulator/tree/maintenance/v2.1 <- This branch also does not have it.