Issue #2797: Allowed zero as valid value for ImportExport attribute s…

…election.

Kernel/Output/HTML/ImportExport/LayoutSelection.pm

@@ -2,7 +2,7 @@
 # OTOBO is a web-based ticketing system for service organisations.
 # --
 # Copyright (C) 2001-2020 OTRS AG, https://otrs.com/
-# Copyright (C) 2019-2023 Rother OSS GmbH, https://otobo.de/
+# Copyright (C) 2019-2024 Rother OSS GmbH, https://otobo.de/
 # --
 # This program is free software: you can redistribute it and/or modify it under
 # the terms of the GNU General Public License as published by the Free Software
@@ -88,7 +88,9 @@ sub FormInputCreate {
 
     # set default value
     $Param{Prefix} ||= '';
-    $Param{Value}  ||= $Param{Item}->{Input}->{ValueDefault};
+
+    # zero is a valid value (occurs e.g. with selecting 'No' for Attribute IncludeColumnHeaders)
+    $Param{Value} //= $Param{Item}->{Input}->{ValueDefault};
 
     if ( $Param{Value} && $Param{Value} =~ m{ ##### }xms ) {
         my @Values = split /#####/, $Param{Value};