The BUILD_WITH_KF5 option was checked with DEFINED, so passing -DBUILD_WITH_KF5=OFF still entered the KF5 setup path.
Skip the KF5 setup when disabled and provide small Qt-only replacements for the KDE color widgets used by .ui files in that build mode.
Assisted-by: pi coding agent / Mika (OpenAI GPT-5.5)
The .desktop, MIME package, and appdata install rules are
freedesktop.org conventions and only apply on Linux. Wrapping
them in if(UNIX AND NOT APPLE) prevents a configure failure on
macOS and Windows where QET_APPDATA_PATH and QET_MIME_PACKAGE_PATH
are not defined.
Also replace the hardcoded share/mime/packages path with
${QET_MIME_PACKAGE_PATH} for consistency with
paths_compilation_installation.cmake.
No change to Linux build behaviour.
Those desktop MIME types were needed only with KDE up to 3.x, as it
used to have its own desktop-based MIME type system. KDE 3 is EOL for
many years now, and there are already XDG MIME types.
These files are the bare XML definitions, and they are automatically
generated by update-mime-database (part of shared-mime-info) on update
(e.g. by distro hooks) or manually. Keeping them in the sources, and
installing them, is definitely not correct, as qelectrotech.xml is
their canonical definition.
Hence, drop them from the sources, together with references to them.
Gerhard Schwanzer