diff -pruN 4.12.1+dfsg-3/debian/changelog 4.12.1+dfsg-3ubuntu1/debian/changelog
--- 4.12.1+dfsg-3/debian/changelog	2019-10-31 09:32:01.000000000 +0000
+++ 4.12.1+dfsg-3ubuntu1/debian/changelog	2019-11-01 13:24:24.000000000 +0000
@@ -1,3 +1,10 @@
+python-qt4 (4.12.1+dfsg-3ubuntu1) focal; urgency=medium
+
+  * Revert dropping D-Bus mainloop packages, as we still have dependencies
+    on these in Ubuntu.
+
+ -- Rik Mills <rikmills@kde.org>  Fri, 01 Nov 2019 13:24:24 +0000
+
 python-qt4 (4.12.1+dfsg-3) unstable; urgency=medium
 
   [ Ondřej Nový ]
diff -pruN 4.12.1+dfsg-3/debian/clean 4.12.1+dfsg-3ubuntu1/debian/clean
--- 4.12.1+dfsg-3/debian/clean	2019-10-31 09:32:01.000000000 +0000
+++ 4.12.1+dfsg-3ubuntu1/debian/clean	2019-11-01 13:21:02.000000000 +0000
@@ -1,3 +1,4 @@
+debian/python-qt4-dbus.install
 designer/python.pro
 designer/Makefile
 sip/pyqt-gpl.sip5
diff -pruN 4.12.1+dfsg-3/debian/control 4.12.1+dfsg-3ubuntu1/debian/control
--- 4.12.1+dfsg-3/debian/control	2019-10-31 09:32:01.000000000 +0000
+++ 4.12.1+dfsg-3ubuntu1/debian/control	2019-11-01 13:21:02.000000000 +0000
@@ -9,6 +9,7 @@ Build-Depends: debhelper-compat (= 10),
                dh-strip-nondeterminism,
                dpkg-dev (>= 1.16.1~),
                libicu-dev,
+               libdbus-1-dev (>= 1.0.2),
                libqt4-dev (>= 4:4.8.0-1~),
                libqt4-opengl-dev,
                libqtassistantclient-dev,
@@ -16,6 +17,11 @@ Build-Depends: debhelper-compat (= 10),
                python-all-dev (>= 2.7.5-1~),
                python3-all-dbg,
                python3-all-dev (>= 3.3),
+               python-dbus (>= 1.0.0~),
+               python-dbus-dbg,
+               python3-dbus,
+               python3-dbus-dbg,
+               python-dbus-dev,
                python-sip-dbg,
                python-sip-dev (>= 4.19.1+dfsg-2~),
                python3-sip-dbg,
@@ -89,6 +95,54 @@ Description: Python3 bindings for Qt4 (d
  .
  This package contains the extensions built for the Python3 debug interpreter.
 
+Package: python-qt4-dbus
+Architecture: any
+Depends: python-dbus (>= 0.84.0-2~),
+         ${misc:Depends},
+         ${python:Depends},
+         ${shlibs:Depends}
+Description: D-Bus Support for PyQt4
+ The D-Bus module of PyQt4 provides integration of PyQt4 applications
+ with the D-Bus main loop.
+
+Package: python-qt4-dbus-dbg
+Architecture: any
+Section: debug
+Depends: python-dbg,
+         python-dbus-dbg,
+         python-qt4-dbus (= ${binary:Version}),
+         ${misc:Depends},
+         ${shlibs:Depends}
+Description: D-Bus Support for PyQt4 (debug extensions)
+ The D-Bus module of PyQt4 provides integration of PyQt4 applications
+ with the D-Bus main loop.
+ .
+ This package contains the extensions built for the Python debug interpreter.
+
+Package: python3-dbus.mainloop.qt
+Architecture: any
+Depends: python3-dbus,
+         ${misc:Depends},
+         ${python3:Depends},
+         ${shlibs:Depends}
+Description: D-Bus Support for PyQt4 with Python 3
+ The D-Bus module of PyQt4 provides integration of PyQt4 applications
+ with the D-Bus main loop for Python 3
+
+Package: python3-dbus.mainloop.qt-dbg
+Architecture: any
+Section: debug
+Depends: python3-dbg,
+         python3-dbus-dbg,
+         python3-dbus.mainloop.qt (= ${binary:Version}),
+         ${misc:Depends},
+         ${shlibs:Depends}
+Description: D-Bus Support for PyQt4 (debug extensions for Python 3)
+ The D-Bus module of PyQt4 provides integration of PyQt4 applications
+ with the D-Bus main loop for Python 3
+ .
+ This package contains the extensions built for the Python debug interpreter.
+
 Package: python-qt4-gl
 Architecture: any
 Depends: python-qt4 (= ${binary:Version}),
diff -pruN 4.12.1+dfsg-3/debian/pyqtconfig_py3.py 4.12.1+dfsg-3ubuntu1/debian/pyqtconfig_py3.py
--- 4.12.1+dfsg-3/debian/pyqtconfig_py3.py	2019-10-31 09:32:01.000000000 +0000
+++ 4.12.1+dfsg-3ubuntu1/debian/pyqtconfig_py3.py	2019-11-01 13:24:24.000000000 +0000
@@ -2,3 +2,4 @@
 # build.
 
 import sys
+
diff -pruN 4.12.1+dfsg-3/debian/rules 4.12.1+dfsg-3ubuntu1/debian/rules
--- 4.12.1+dfsg-3/debian/rules	2019-10-31 09:32:01.000000000 +0000
+++ 4.12.1+dfsg-3ubuntu1/debian/rules	2019-11-01 13:21:02.000000000 +0000
@@ -4,6 +4,9 @@
 
 export DH_OPTIONS
 
+py_dbusmoddir = $(shell python$(1) -c 'import dbus.mainloop; print dbus.mainloop.__path__[0]')
+py3_dbusmoddir = $(shell python3 -c 'import dbus.mainloop; print(dbus.mainloop.__path__[0])')
+
 export QMAKESPEC=linux-g++
 
 CFLAGS=
@@ -60,6 +63,7 @@ build-%/configure-stamp:
 	cd build-$* && python$* ../configure.py $(SHARED_CONFIGURE_OPTIONS) \
 			-m $(shell python$*-config --configdir) \
 			-d /usr/lib/python$*/dist-packages \
+			--dbus /usr/include/dbus-1.0 \
 			$(if $(filter $(DEFAULT_PYTHON),$*),,--no-designer-plugin)
 	touch $@
 
@@ -101,6 +105,8 @@ install-arch: build-arch
 	dh_prep -a
 	dh_installdirs -a
 	sed -i -e '/strip/ d' $(CURDIR)/build-$(DEFAULT_PYTHON)/designer/Makefile
+	rm -f $(CURDIR)/debian/python-qt4-dbus.install
+	rm -f $(CURDIR)/debian/python3-dbus.mainloop.qt.install
 	# This is needed to enforce that the install-arch-% rules are
 	# not run in parallel. Both rules install into the same directory,
 	# and therefore might try to access the same files at the same time.
@@ -131,10 +137,21 @@ d3_qt4_dbg = debian/python3-pyqt4-dbg
 install-arch-3.%:
 	$(MAKE) -C build-3.$* install \
 		INSTALL_ROOT=$(CURDIR)/debian/tmp DESTDIR=$(CURDIR)/debian/tmp
+	if [ -e $(CURDIR)/debian/tmp$(call py3_dbusmoddir,3.$*)/qt.so ]; then \
+		mkdir -p $(CURDIR)/debian/tmp/usr/lib/python3.$*/dist-packages/dbus/mainloop; \
+		mv $(CURDIR)/debian/tmp$(call py3_dbusmoddir,3.$*)/qt.so \
+		$(CURDIR)/debian/tmp/usr/lib/python3.$*/dist-packages/dbus/mainloop; \
+		echo 'usr/lib/python3.$*/dist-packages/dbus/' >> $(CURDIR)/debian/python3-dbus.mainloop.qt.install;\
+	fi
 	mv $(CURDIR)/debian/tmp/usr/lib/python3.$*/dist-packages/PyQt4/pyqtconfig.py \
 		$(CURDIR)/debian/tmp/usr/lib/python3.$*/dist-packages/PyQt4/pyqtconfig_nd$*.py
 
 	$(MAKE) -C dbg-build-3.$* install DESTDIR=$(CURDIR)/$(d3_qt4_dbg)
+	if [ -e $(CURDIR)/$(d3_qt4_dbg)$(call py3_dbusmoddir,3.$*)/qt.so ]; then \
+		mkdir -p $(CURDIR)/debian/python3-dbus.mainloop.qt-dbg/usr/lib/python3.$*/dist-packages/dbus/mainloop; \
+		mv $(CURDIR)/debian/python3-pyqt4-dbg$(call py3_dbusmoddir,3.$*)/qt.so \
+		$(CURDIR)/debian/python3-dbus.mainloop.qt-dbg/usr/lib/python3.$*/dist-packages/dbus/mainloop; \
+	fi
 
 	# Don't initiate the uic/widget-plugins
 	touch $(CURDIR)/debian/tmp/usr/lib/python3.$*/dist-packages/PyQt4/uic/widget-plugins/.noinit
@@ -171,6 +188,13 @@ install-arch-%:
 	mv $(d_qt4_dbg)/usr/lib/python$*/dist-packages/PyQt4/QtSql.so \
 		debian/python-qt4-sql-dbg/usr/lib/python$*/dist-packages/PyQt4
 
+	if [ -e $(d_qt4_dbg)$(call py_dbusmoddir,$*)/qt.so ]; then \
+		mkdir -p debian/python-qt4-dbus-dbg/$(call py_dbusmoddir,$*);\
+		mv $(d_qt4_dbg)$(call py_dbusmoddir,$*)/qt.so \
+			debian/python-qt4-dbus-dbg$(call py_dbusmoddir,$*);\
+		echo '$(call py_dbusmoddir,$*)/*' >> $(CURDIR)/debian/python-qt4-dbus.install;\
+	fi
+
 
 clean:
 	dh_testdir
@@ -198,6 +222,7 @@ ifeq (,$(findstring -i, $(DH_OPTIONS)))
 	DH_OPTIONS= dh_strip -ppyqt4-dev-tools
 	set -e; \
 	for p in python-qt4 python3-pyqt4 \
+		python-qt4-dbus python3-dbus.mainloop.qt \
 		python-qt4-gl \
 		python-qt4-sql python3-pyqt4.qtsql \
 		python3-pyqt4.qtopengl \
@@ -215,6 +240,7 @@ endif
 	rm -rf $(CURDIR)/debian/python3-pyqt4-dbg/usr/bin
 	rm -rf $(CURDIR)/debian/python3-pyqt4-dbg/usr/share/sip
 	rm -rf $(CURDIR)/debian/python3-pyqt4-dbg/usr/lib/python3/dist-packages/PyQt4/uic
+	rm -rf $(CURDIR)/debian/python3-pyqt4-dbg/usr/lib/python3/dist-packages/dbus
 
 	dh_strip_nondeterminism
 	dh_fixperms
