this is a tough one as it maybe broken either way, but binary_to_desktop_file currently follows symlinks of the binary file passed in, which in the case of firefox on openSUSE ends up pointing to /usr/lib64/firefox.sh, which in turn leads to it searching for "firefox.sh" in the desktop files which is not found.
The line in question is
binary="`readlink -f "$binary"`"
maybe this is a bug in firefox's desktop file (exec'ing a symlink rather then the binary) but either way I thought i'd look for a second opinion on which is more right.
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