Also, since I realized there's no way to change the GUID and still delete the previous version on upgrade, I'm adding an update.rdf entry that will disable old versions with a blank extension and force people to reinstall, since otherwise they'd end up with both Scholar and Zotero installed at once, which, as you know, would create a time paradox, the results of which could start a chain reaction that would unravel the very fabric of the space-time continuum and destroy the entire universe.
Anyone on an XPI install should go to Add-ons and delete their version and fetch a new one from http://chnm.gmu.edu/firefoxscholar/download/zotero-dev.xpi
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