On Linux, when building a package from the predefined app image (--app-image) with the installation directory in the "/usr" subtree (--install-dir=/usr), the libapplauncher.so is placed at "/usr/lib/${PACKAGE_NAME}/libapplauncher.so" location instead of "/usr/lib/${PACKAGE_NAME}/lib/libapplauncher.so".

The issue was spotted in the output of the PostImageScriptTest.testWithInstallDir(EXTERNAL_APP_IMAGE; verifyAppImageContents) test:

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Command [PID: <pid>]:
    ldd /tmp/jdk.jpackage/image/usr/lib/withinstalldirpostimagescripttest/lib/libapplauncher.so
Output:
    ldd: warning: you do not have execution permission for `/tmp/jdk.jpackage/image/usr/lib/withinstalldirpostimagescripttest/lib/libapplauncher.so'
     linux-vdso.so.1 (0xHEX)
     libdl.so.2 => /lib64/libdl.so.2 (0xHEX)
     libpthread.so.0 => /lib64/libpthread.so.0 (0xHEX)
     libm.so.6 => /lib64/libm.so.6 (0xHEX)
     libc.so.6 => /lib64/libc.so.6 (0xHEX)
     /lib64/ld-linux-x86-64.so.2 (0xHEX)
Returned: 0
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