'Is the document modified.
Run a strict check against all node properties as they were
at the time when the last call to `setModified(True)` was made.'

def isModifiedStrict(self):

    propertiesChanged = (self.__cleanProperties != node_properties(self.__scheme))
    log.debug('Modified    strict    check    (modified    flag:    %s,    undo    stack    clean:    %s,    properties:    %s)', self.__modified, self.__undoStack.isClean(), propertiesChanged)
    return (self.isModified() or propertiesChanged)
