Working on a Qt app, I checked Focuswriter as its Qt too. Regshotting it I discovered that lit leaves the following keys behind:
HKCU\Software\Trolltech HKCU\Software\Trolltech\OrganizationDefaults HKCU\Software\Trolltech\OrganizationDefaults\Qt Factory Cache 4.8 HKCU\Software\Trolltech\OrganizationDefaults\Qt Factory Cache 4.8\com.trolltech.Qt.QImageIOHandlerFactoryInterface: HKCU\Software\Trolltech\OrganizationDefaults\Qt Factory Cache 4.8\com.trolltech.Qt.QImageIOHandlerFactoryInterface:\D: HKCU\Software\Trolltech\OrganizationDefaults\Qt Factory Cache 4.8\com.trolltech.Qt.QImageIOHandlerFactoryInterface:\D:\PortableApps HKCU\Software\Trolltech\OrganizationDefaults\Qt Factory Cache 4.8\com.trolltech.Qt.QImageIOHandlerFactoryInterface:\D:\PortableApps\FocusWriterPortable HKCU\Software\Trolltech\OrganizationDefaults\Qt Factory Cache 4.8\com.trolltech.Qt.QImageIOHandlerFactoryInterface:\D:\PortableApps\FocusWriterPortable\App HKCU\Software\Trolltech\OrganizationDefaults\Qt Factory Cache 4.8\com.trolltech.Qt.QImageIOHandlerFactoryInterface:\D:\PortableApps\FocusWriterPortable\App\FocusWriter HKCU\Software\Trolltech\OrganizationDefaults\Qt Factory Cache 4.8\com.trolltech.Qt.QImageIOHandlerFactoryInterface:\D:\PortableApps\FocusWriterPortable\App\FocusWriter\imageformats HKCU\Software\Trolltech\OrganizationDefaults\Qt Plugin Cache 4.8.false HKCU\Software\Trolltech\OrganizationDefaults\Qt Plugin Cache 4.8.false\D: HKCU\Software\Trolltech\OrganizationDefaults\Qt Plugin Cache 4.8.false\D:\PortableApps HKCU\Software\Trolltech\OrganizationDefaults\Qt Plugin Cache 4.8.false\D:\PortableApps\FocusWriterPortable HKCU\Software\Trolltech\OrganizationDefaults\Qt Plugin Cache 4.8.false\D:\PortableApps\FocusWriterPortable\App HKCU\Software\Trolltech\OrganizationDefaults\Qt Plugin Cache 4.8.false\D:\PortableApps\FocusWriterPortable\App\FocusWriter HKCU\Software\Trolltech\OrganizationDefaults\Qt Plugin Cache 4.8.false\D:\PortableApps\FocusWriterPortable\App\FocusWriter\imageformats
The FocusWriterPortable.ini reads:
[QtKeysCleanup] 1="Qt Factory Cache 4.7\com.trolltech.Qt.QImageIOHandlerFactoryInterface:" 2="Qt Plugin Cache 4.7.false"
but it should probably be updated to version 4.8:
[QtKeysCleanup] 1="Qt Factory Cache 4.8\com.trolltech.Qt.QImageIOHandlerFactoryInterface:" 2="Qt Plugin Cache 4.8.false"
This is fixed in FocusWriter Portable 1.4.6
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