diff --git a/cantor.spec b/cantor.spec
index c2c5718..6b825b8 100644
--- a/cantor.spec
+++ b/cantor.spec
@@ -1,5 +1,5 @@
 Name:          cantor
-Version:       21.08.1
+Version:       21.08.2
 Release:       1mamba
 Summary:       KDE Frontend to Mathematical Software
 Group:         Graphical Desktop/Applications/Educational
@@ -15,6 +15,7 @@ BuildRequires: gcc-fortran
 BuildRequires: glibc-devel
 BuildRequires: libQt5WebEngine-devel
 BuildRequires: libR-devel
+BuildRequires: libX11-devel
 BuildRequires: libanalitza-devel
 BuildRequires: libattica5-devel
 BuildRequires: libgcc
@@ -151,6 +152,9 @@ exit 0
 %{_libdir}/cmake/Cantor/Cantor*.cmake
 
 %changelog
+* Fri Oct 08 2021 Automatic Build System <autodist@mambasoft.it> 21.08.2-1mamba
+- automatic version update by autodist
+
 * Thu Sep 02 2021 Automatic Build System <autodist@mambasoft.it> 21.08.1-1mamba
 - automatic version update by autodist