Fritzing 0.9.3b fails to launch with its built-in Qt framework

UPDATE

The environment variable which causes the issue is QT_PLUGIN_PATH being exported system-wide at the time of user login.

I have a variety of Qt applications where having QT_PLUGIN_PATH set is not an issue. So, this Fritzing 0.9.3b non-launch behavior was a surprise.

One would expect that the application's executable path and/or qt.conf included in the application bundle would take precedence over QT_PLUGIN_PATH .

When the application is run, Qt will first treat the application's executable directory as the base directory for searching for plugins.

See Qt Documentation > Deploying Plugins

An alternate (maybe more robust) strategy might be to use QCoreApplication::addLibraryPath() or QCoreApplication::setLibraryPath().

However, I also learned that this note has been added to the Qt documentation ...

QT_PLUGIN_PATH should not be exported as a system-wide environment variable since it can interfere with other Qt installations.

So, while Fritzing might have ways to launch more robustly in the presence of QT_PLUGIN_PATH being preset, the user (like my situation) can also resolve the issue by not setting QT_PLUGIN_PATH as a system-wide variable.

Cheers.