KDE relies on QStandardPath for shared resource lookups, which fails when running on non Linux systems

KDE currently relies on QStandardPath for shared resource lookups.

QStandardPaths DataLocation, ConfigLocation, etc. return platform specific defaults but on Linux they also return the values from XDG_DATA_DIRS, XDG_CONFIG_DIRS, etc. so when installing applications in non default paths applications that use QStandardPaths can still find their data/libraries/plugins/config, etc.

QStandardPaths is not changable at runtime on OS X and Windows, which means the strategy of using QStandardPaths fails when KDE is deployed though eg homebrew.