STEPS TO REPRODUCE
1. download the TIFF file attached in bug 404794 
2. open download location with dolphin
3. enable preview in Dolphin

OBSERVED RESULT
plasma notifies about kinit5 crash

EXPECTED RESULT
no crash notification

SOFTWARE/OS VERSIONS
Operating System: Arch Linux 
KDE Plasma Version: 5.15.2
KDE Frameworks Version: 5.55.0
Qt Version: 5.12.1



Thread 3 (Thread 0x7f8af3aae700 (LWP 26075)):
#0  0x00007f8afb271afc in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1  0x00007f8af409dc94 in  () at /usr/lib/dri/i965_dri.so
#2  0x00007f8af409d9b8 in  () at /usr/lib/dri/i965_dri.so
#3  0x00007f8afb26ba9d in start_thread () at /usr/lib/libpthread.so.0
#4  0x00007f8afc03ab23 in clone () at /usr/lib/libc.so.6

Thread 2 (Thread 0x7f8af1e6b700 (LWP 26076)):
#0  0x00007f8afc02fc21 in poll () at /usr/lib/libc.so.6
#1  0x00007f8af8c58540 in  () at /usr/lib/libglib-2.0.so.0
#2  0x00007f8af8c5862e in g_main_context_iteration () at /usr/lib/libglib-2.0.so.0
#3  0x00007f8afc3d5d04 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x7f8ae4000b20, flags=...) at kernel/qeventdispatcher_glib.cpp:424
#4  0x00007f8afc37eb2c in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>)
    (this=this@entry=0x7f8af1e6ad70, flags=..., flags@entry=...)
    at ../../include/QtCore/../../src/corelib/global/qflags.h:140
#5  0x00007f8afc1c2569 in QThread::exec()
    (this=this@entry=0x7f8af77f8080 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>) at ../../include/QtCore/../../src/corelib/global/qflags.h:120
#6  0x00007f8af777cba6 in QDBusConnectionManager::run()
    (this=0x7f8af77f8080 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>)
    at qdbusconnection.cpp:178
#7  0x00007f8afc1c396c in QThreadPrivate::start(void*) (arg=0x7f8af77f8080 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>) at thread/qthread_unix.cpp:361
#8  0x00007f8afb26ba9d in start_thread () at /usr/lib/libpthread.so.0
#9  0x00007f8afc03ab23 in clone () at /usr/lib/libc.so.6

Thread 1 (Thread 0x7f8af81da800 (LWP 26074)):
#0  0x00007f8afbf76d7f in raise () at /usr/lib/libc.so.6
#1  0x00007f8afce03bcf in KCrash::defaultCrashHandler(int) () at /usr/lib/libKF5Crash.so.5
#2  0x00007f8afbf76e00 in <signal handler called> () at /usr/lib/libc.so.6
#3  0x00007f8af01ed50b in  () at /usr/lib/libtiff.so.5
#4  0x00007f8af01fce22 in TIFFReadScanline () at /usr/lib/libtiff.so.5
#5  0x00007f8af082dc17 in  () at /usr/lib/qt/plugins/imageformats/libqtiff.so
#6  0x00007f8afc7c5f76 in QImageReader::read(QImage*) (this=0x7ffcf15d8788, image=0x7ffcf15d8730) at image/qimagereader.cpp:1261
#7  0x00007f8afc7c65d6 in QImageReader::read() (this=this@entry=0x7ffcf15d8788) at image/qimagereader.cpp:1202
#8  0x00007f8afc7a0b49 in QImage::load(QString const&, char const*) (this=this@entry=0x7ffcf15d88a0, fileName=..., format=format@entry=0x0) at image/qimage.cpp:3559
#9  0x00007f8ae0e66146 in ImageCreator::create(QString const&, int, int, QImage&) (this=this@entry=0x5636dba43950, path=..., img=...) at /usr/src/debug/kio-extras-18.12.2/thumbnail/imagecreator.cpp:36
#10 0x00007f8afce4ee99 in ThumbnailProtocol::get(QUrl const&) (this=0x7ffcf15d8aa0, url=...) at /usr/include/qt/QtCore/qflags.h:120
#11 0x00007f8af7dde9bf in KIO::SlaveBase::dispatch(int, QByteArray const&) () at /usr/lib/libKF5KIOCore.so.5
#12 0x00007f8af7ddf19e in KIO::SlaveBase::dispatchLoop() () at /usr/lib/libKF5KIOCore.so.5
#13 0x00007f8afce4c4a3 in kdemain(int, char**) (argc=<optimized out>, argv=<optimized out>) at /usr/src/debug/kio-extras-18.12.2/thumbnail/thumbnail.cpp:138
#14 0x00005636d9cb6458 in launch(int, char const*, char const*, char const*, int, char const*, bool, char const*, bool, char const*) (argc=4, _name=0x5636db601a38 "/usr/lib/qt/plugins/kf5/kio/thumbnail.so", args=<optimized out>, cwd=<optimized out>, envc=0, envs=<optimized out>, reset_env=false, tty=0x0, avoid_loops=false, startup_id_str=0x5636d9cb919e "0") at /usr/src/debug/kinit-5.55.0/src/kdeinit/kinit.cpp:706
#15 0x00005636d9cb7552 in handle_launcher_request(int, char const*) (sock=8, who=<optimized out>) at /usr/src/debug/kinit-5.55.0/src/kdeinit/kinit.cpp:1146
#16 0x00005636d9cb7efd in handle_requests(pid_t) (waitForPid=0) at /usr/src/debug/kinit-5.55.0/src/kdeinit/kinit.cpp:1339
#17 0x00005636d9cb2b7a in main(int, char**) (argc=5, argv=<optimized out>) at /usr/src/debug/kinit-5.55.0/src/kdeinit/kinit.cpp:1785