diff -Nru synfig-1.4.0+dfsg/debian/changelog synfig-1.4.0+dfsg/debian/changelog
--- synfig-1.4.0+dfsg/debian/changelog	2021-01-12 06:21:12.000000000 +0000
+++ synfig-1.4.0+dfsg/debian/changelog	2021-09-14 17:00:38.000000000 +0000
@@ -1,3 +1,9 @@
+synfig (1.4.0+dfsg-2+rpi1) bookworm-staging; urgency=medium
+
+  * Add upstream patch for mlt++7 ( Closes: 993832 )
+
+ -- Peter Michael Green <plugwash@raspbian.org>  Tue, 14 Sep 2021 17:00:38 +0000
+
 synfig (1.4.0+dfsg-2) unstable; urgency=medium
 
   * dev: added missing dependencies.
diff -Nru synfig-1.4.0+dfsg/debian/patches/mlt++7.patch synfig-1.4.0+dfsg/debian/patches/mlt++7.patch
--- synfig-1.4.0+dfsg/debian/patches/mlt++7.patch	1970-01-01 00:00:00.000000000 +0000
+++ synfig-1.4.0+dfsg/debian/patches/mlt++7.patch	2021-09-14 17:00:16.000000000 +0000
@@ -0,0 +1,32 @@
+Patch for mlt++7 in Debian synfig package, created by defuzzing the upstream
+commit described below.
+
+commit 54ba18f2ff9a222b1bd8eb01f04cd88d4a54e188
+Author: rodolforg <rodolforg@users.noreply.github.com>
+Date:   Mon Sep 13 04:55:56 2021 -0300
+
+    Added support MLT++-7 in Autotools (#2306)
+
+Index: synfig-1.4.0+dfsg/synfig-core/configure.ac
+===================================================================
+--- synfig-1.4.0+dfsg.orig/synfig-core/configure.ac
++++ synfig-1.4.0+dfsg/synfig-core/configure.ac
+@@ -396,10 +396,15 @@ PKG_CHECK_MODULES(LIBPANGO, pango pangoc
+ 	AC_MSG_ERROR([ ** You need to install pango])
+ ])
+ 
+-PKG_CHECK_MODULES(MLTPP, mlt++,,[
+-	AC_MSG_ERROR([ ** You need to install mlt++.])
++PKG_CHECK_MODULES(MLTPP, mlt++-7,[
++	CONFIG_DEPS="$CONFIG_DEPS mlt++-7"
++],[
++	PKG_CHECK_MODULES(MLTPP, mlt++,[
++		CONFIG_DEPS="$CONFIG_DEPS mlt++"
++	],[
++		AC_MSG_ERROR([ ** You need to install mlt++.])
++	])
+ ])
+-CONFIG_DEPS="$CONFIG_DEPS mlt++"
+ 
+ AX_BOOST_BASE([1.53.0],,AC_MSG_ERROR([ ** You need to install Boost >= 1.53.0]))
+ #AX_BOOST_SYSTEM
diff -Nru synfig-1.4.0+dfsg/debian/patches/series synfig-1.4.0+dfsg/debian/patches/series
--- synfig-1.4.0+dfsg/debian/patches/series	2021-01-11 14:33:44.000000000 +0000
+++ synfig-1.4.0+dfsg/debian/patches/series	2021-09-14 16:59:18.000000000 +0000
@@ -1 +1,2 @@
 strip-build-date.patch
+mlt++7.patch