/usr/ is in libklatexformula4-dev 4.0.0-3.
This file is owned by root:root, with mode 0o755.
..
/usr/include/
/usr/include/klfbackend/
/usr/include/klfbackend/klfbackend.h
/usr/include/klfbackend/klfblockprocess.h
/usr/include/klfbackend/klffilterprocess.h
/usr/include/klfbackend/klflatexpreviewthread.h
/usr/include/klfbackend/klfuserscript.h
/usr/include/klftools/
/usr/include/klftools/klfadvancedconfigeditor.h
/usr/include/klftools/klfcolorchooser.h
/usr/include/klftools/klfconfigbase.h
/usr/include/klftools/klfdatautil.h
/usr/include/klftools/klfdebug.h
/usr/include/klftools/klfdefs.h
/usr/include/klftools/klfdisplaylabel.h
/usr/include/klftools/klfenumlistwidget.h
/usr/include/klftools/klffactory.h
/usr/include/klftools/klfflowlayout.h
/usr/include/klftools/klfflowlistwidget.h
/usr/include/klftools/klfguiutil.h
/usr/include/klftools/klfitemviewsearchtarget.h
/usr/include/klftools/klfiteratorsearchable.h
/usr/include/klftools/klflatexedit.h
/usr/include/klftools/klfpathchooser.h
/usr/include/klftools/klfpixmapbutton.h
/usr/include/klftools/klfpobj.h
/usr/include/klftools/klfpobjeditwidget.h
/usr/include/klftools/klfprogerr.h
/usr/include/klftools/klfrelativefont.h
/usr/include/klftools/klfsearchbar.h
/usr/include/klftools/klfsidewidget.h
/usr/include/klftools/klfsysinfo.h
/usr/include/klftools/klfunitinput.h
/usr/include/klftools/klfutil.h
/usr/include/klftools/qtcolortriangle.h
/usr/lib/
/usr/lib/x86_64-linux-gnu/
/usr/lib/x86_64-linux-gnu/qt5/
/usr/lib/x86_64-linux-gnu/qt5/plugins/
/usr/lib/x86_64-linux-gnu/qt5/plugins/designer/
/usr/lib/x86_64-linux-gnu/qt5/plugins/designer/libklftoolsdesplugin.so
/usr/share/
/usr/share/doc/
/usr/share/doc/libklatexformula4-dev/
/usr/share/doc/libklatexformula4-dev/copyright
/usr/lib/x86_64-linux-gnu/libklfbackend.so
/usr/lib/x86_64-linux-gnu/libklftools.so
/usr/share/doc/libklatexformula4-dev/changelog.Debian.gz