'save; seems not to work

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RapidWeaver Version: *6.3.4
System Version: *10.11
mac pro early 2008

Issue:
choosing ‘save’ has seems to have no effect. If ‘save’ then export, rapid weaver warns the project is unsaved

Expected Result:
after saving and going immediately to export, would not expect a warning that the project unsaved

Additional Links:
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