diff --git a/cad/PrusaSlicer/Makefile b/cad/PrusaSlicer/Makefile
index 11926ada11cd..9684196c921b 100644
--- a/cad/PrusaSlicer/Makefile
+++ b/cad/PrusaSlicer/Makefile
@@ -1,38 +1,38 @@
 PORTNAME=	PrusaSlicer
 DISTVERSIONPREFIX=version_
 DISTVERSION=	2.3.0
-PORTREVISION=	10
+PORTREVISION=	11
 CATEGORIES=	cad
 
 MAINTAINER=	teodorsigaev@gmail.com
 COMMENT=	Slicing application for 3D printers
 
 LICENSE=	AGPLv3
 LICENSE_FILE=	${WRKSRC}/LICENSE
 
 LIB_DEPENDS=	libtbb.so:devel/tbb \
 		libboost_log.so:devel/boost-libs \
 		libImath.so:math/Imath \
 		libnlopt.so:math/nlopt \
 		libcurl.so:ftp/curl \
 		libexpat.so:textproc/expat2 \
 		libopenvdb.so:misc/openvdb \
 		libgmp.so:math/gmp \
 		libmpfr.so:math/mpfr \
 		libdbus-1.so:devel/dbus \
 		libpng.so:graphics/png
 BUILD_DEPENDS=	cereal>=1.3.0.10:devel/cereal \
 		cgal>=5.0.2:math/cgal
 
 USES=		cmake desktop-file-utils eigen:3 gettext gl iconv pkgconfig
 CMAKE_ARGS+=	-DwxWidgets_CONFIG_EXECUTABLE="${WX_CONFIG}" \
 		-DSLIC3R_GTK=3 \
 		-DSLIC3R_FHS=1
 USE_GITHUB=	yes
 GH_ACCOUNT=	prusa3d
 USE_WX=		3.1
 USE_GL=		gl glu glew
 
 PORTDATA=	*
 
 .include <bsd.port.mk>
diff --git a/cad/PrusaSlicer/files/patch-src_slic3r_GUI_OpenGLManager.cpp b/cad/PrusaSlicer/files/patch-src_slic3r_GUI_OpenGLManager.cpp
new file mode 100644
index 000000000000..ede8451a494f
--- /dev/null
+++ b/cad/PrusaSlicer/files/patch-src_slic3r_GUI_OpenGLManager.cpp
@@ -0,0 +1,12 @@
+--- src/slic3r/GUI/OpenGLManager.cpp.orig	2021-08-03 16:17:35 UTC
++++ src/slic3r/GUI/OpenGLManager.cpp
+@@ -237,7 +237,8 @@ bool OpenGLManager::init_gl()
+     if (!m_gl_initialized) {
+         if (glewInit() != GLEW_OK) {
+             BOOST_LOG_TRIVIAL(error) << "Unable to init glew library";
+-            return false;
++	    /* Ugly fix for https://github.com/prusa3d/PrusaSlicer/issues/6396 */
++            //return false;
+         }
+         m_gl_initialized = true;
+         if (GLEW_EXT_texture_compression_s3tc)