Gets a value indicating whether the formatting is fixed in the class instance level.

If true, any formatting changes on an ancestor level of the same class will be ignored.

If false, changing a property on an ancestor level will apply to this level too.

For example, changing a property of Fill on style level will change that property only for those Runs that have IsFixed equal to false.

Sets all properties to their default values.

Also sets IsFixed to true if any properties of this class are defined on an ancestor level.

Resets all properties to their inherited values.

Also sets IsFixed to false.