diff --git a/cantor.spec b/cantor.spec
index 38f1f83..2a9676a 100644
--- a/cantor.spec
+++ b/cantor.spec
@@ -1,6 +1,6 @@
 Name:          cantor
 Version:       20.08.0
-Release:       1mamba
+Release:       2mamba
 Summary:       KDE Frontend to Mathematical Software
 Group:         Graphical Desktop/Applications/Educational
 Vendor:        openmamba
@@ -11,10 +11,10 @@ Source:        http://download.kde.org/stable/release-service/%{version}/src/can
 Patch0:        cantor-20.04.0-luajit-5.1.patch
 License:       GPL
 ## AUTOBUILDREQ-BEGIN
-BuildRequires: R
 BuildRequires: gcc-fortran
 BuildRequires: glibc-devel
 BuildRequires: ldconfig
+BuildRequires: libR-devel
 BuildRequires: libanalitza-devel
 BuildRequires: libattica5-devel
 BuildRequires: libgcc
@@ -52,6 +52,8 @@ BuildRequires: libspectre-devel
 BuildRequires: libstdc++6-devel
 BuildRequires: libsyntax-highlighting-devel
 ## AUTOBUILDREQ-END
+BuildRequires: libpoppler-devel >= 20.08.0
+BuildRequires: libpoppler-qt5-devel >= 20.08.0
 BuildRequires: libqalculate-devel >= 2.6.2-1mamba
 BuildRequires: libluajit-devel
 BuildRequires: cmake
@@ -59,6 +61,11 @@ BuildRequires: gcc >= 8.1.0
 #Requires:      kde-workspace
 BuildRoot:     %{_tmppath}/%{name}-%{version}-root
 
+#-- The following OPTIONAL packages have not been found:
+#
+#* Julia, A high-level, high-performance dynamic programming language for technical computing, <https://julialang.org/>
+#Backend to use Julia with Cantor.
+
 %description
 Cantor is a front-end to powerful mathematics and statistics packages.
 Cantor integrates them into the KDE Platform and provides a nice, worksheet-based, graphical user interface.
@@ -163,6 +170,9 @@ exit 0
 %{_libdir}/cmake/Cantor/Cantor*.cmake
 
 %changelog
+* Tue Sep 01 2020 Silvan Calarco <silvan.calarco@mambasoft.it> 20.08.0-2mamba
+- rebuilt with libpoppler 20.08.0
+
 * Sat Aug 15 2020 Automatic Build System <autodist@mambasoft.it> 20.08.0-1mamba
 - automatic version update by autodist