if ($windows) {  ## $windows as set up earlier in the code = TRUE if ($^O eq 'MSWin32' or $^O eq 'MSWin64');
	$ENV{GTK_EXE_PREFIX} = "$ENV{TEMP}\\pdk-$ENV{USERNAME}-$$";
	$ENV{GTK_DATA_PREFIX} = "$ENV{TEMP}\\pdk-$ENV{USERNAME}-$$";
	$ENV{XDG_DATA_DIRS} = "$ENV{TEMP}\\pdk-$ENV{USERNAME}-$$";  ## Has no effect, see above.
}