diff -Nru software-properties-0.98.7/debian/changelog software-properties-0.98.9/debian/changelog
--- software-properties-0.98.7/debian/changelog	2020-02-27 14:38:46.000000000 +0000
+++ software-properties-0.98.9/debian/changelog	2020-04-16 09:57:50.000000000 +0000
@@ -1,3 +1,21 @@
+software-properties (0.98.9) focal; urgency=medium
+
+  * softwareproperties/gtk/SoftwarePropertiesGtk.py:
+    - Gtk is doing something that takes a lock while processing checkbox
+      toggled events, the polkit auth dialog can't be displayed in return,
+      we don't have a proper fix and it might require GTK changes,
+      meanwhile we want a working interface so workaround with a sleep
+      (lp: #1727908)
+
+ -- Sebastien Bacher <seb128@ubuntu.com>  Thu, 16 Apr 2020 11:57:50 +0200
+
+software-properties (0.98.8) focal; urgency=medium
+
+  * Move get_dependencies from SoftwarePropertiesGtk to SoftwareProperties
+    and adjust both Qt and Gtk frontends to use that (LP: #1872551)
+
+ -- Julian Andres Klode <juliank@ubuntu.com>  Thu, 16 Apr 2020 10:41:28 +0200
+
 software-properties (0.98.7) focal; urgency=medium
 
   * softwareproperties/gtk/SimpleGtkbuilderApp.py: Fix a typo in the
diff -Nru software-properties-0.98.7/softwareproperties/gtk/SoftwarePropertiesGtk.py software-properties-0.98.9/softwareproperties/gtk/SoftwarePropertiesGtk.py
--- software-properties-0.98.7/softwareproperties/gtk/SoftwarePropertiesGtk.py	2020-02-27 14:38:46.000000000 +0000
+++ software-properties-0.98.9/softwareproperties/gtk/SoftwarePropertiesGtk.py	2020-04-16 09:57:50.000000000 +0000
@@ -38,6 +38,7 @@
 import logging
 import threading
 import sys
+import time
 
 import gi
 gi.require_version("Gdk", "3.0")
@@ -144,18 +145,6 @@
     return False
 
 
-def get_dependencies(apt_cache, package_name, pattern=None):
-    """ Get the package dependencies, which can be filtered out by a pattern """
-    dependencies = []
-    for or_group in apt_cache[package_name].candidate.dependencies:
-        for dep in or_group:
-            if dep.rawtype in ["Depends", "PreDepends"]:
-                dependencies.append(dep.name)
-    if pattern:
-        dependencies = [ x for x in dependencies if x.find(pattern) != -1 ]
-    return dependencies
-
-
 class SoftwarePropertiesGtk(SoftwareProperties, SimpleGtkbuilderApp):
 
     def __init__(self, datadir=None, options=None, file=None, parent=None):
@@ -847,6 +836,13 @@
 
     def on_isv_source_toggled(self, cell_toggle, path, store):
         """Enable or disable the selected channel"""
+
+        #FIXME Gtk is doing something that takes a lock while processing
+        # the events, the polkit auth dialog can't be displayed in return,
+        # we don't have a proper fix and it might require GTK changes,
+        # meanwhile we want a working interface so workaround with a sleep
+        # https://launchpad.net/bugs/1727908
+        time.sleep(0.3)
         #FIXME cdroms need to disable the comps in the childs and sources
         iter = store.get_iter((int(path),))
         source_entry = store.get_value(iter, STORE_SOURCE)
@@ -1193,7 +1189,7 @@
                 # We need to collect its dependencies, so that
                 # we can uninstall the driver properly.
                 if 'nvidia' in pkg.shortname:
-                    for dep in get_dependencies(self.apt_cache, pkg.shortname, 'nvidia'):
+                    for dep in self.get_dependencies(self.apt_cache, pkg.shortname, 'nvidia'):
                         dep_pkg = self.apt_cache[dep]
                         if dep_pkg.is_installed:
                             removals.append(self.get_package_id(dep_pkg.installed))
diff -Nru software-properties-0.98.7/softwareproperties/qt/SoftwarePropertiesQt.py software-properties-0.98.9/softwareproperties/qt/SoftwarePropertiesQt.py
--- software-properties-0.98.7/softwareproperties/qt/SoftwarePropertiesQt.py	2020-02-27 14:38:46.000000000 +0000
+++ software-properties-0.98.9/softwareproperties/qt/SoftwarePropertiesQt.py	2020-04-16 08:41:28.000000000 +0000
@@ -892,7 +892,7 @@
           # We need to collect its dependencies, so that
           # we can uninstall the driver properly.
           if 'nvidia' in pkg.shortname:
-            for dep in get_dependencies(self.apt_cache, pkg.shortname, 'nvidia'):
+            for dep in self.get_dependencies(self.apt_cache, pkg.shortname, 'nvidia'):
               dep_pkg = self.apt_cache[dep]
               if dep_pkg.is_installed:
                 removals.append(self.get_package_id(dep_pkg.installed))
diff -Nru software-properties-0.98.7/softwareproperties/SoftwareProperties.py software-properties-0.98.9/softwareproperties/SoftwareProperties.py
--- software-properties-0.98.7/softwareproperties/SoftwareProperties.py	2020-02-27 14:38:46.000000000 +0000
+++ software-properties-0.98.9/softwareproperties/SoftwareProperties.py	2020-04-16 08:41:28.000000000 +0000
@@ -866,6 +866,19 @@
     return "%s;%s;%s;" % (ver.package.shortname, ver.version,
                           ver.package.architecture())
 
+
+  @staticmethod
+  def get_dependencies(apt_cache, package_name, pattern=None):
+    """ Get the package dependencies, which can be filtered out by a pattern """
+    dependencies = []
+    for or_group in apt_cache[package_name].candidate.dependencies:
+      for dep in or_group:
+        if dep.rawtype in ["Depends", "PreDepends"]:
+          dependencies.append(dep.name)
+    if pattern:
+      dependencies = [ x for x in dependencies if x.find(pattern) != -1 ]
+    return dependencies
+
 def shortcut_handler(shortcut):
     for factory in _SHORTCUT_FACTORIES:
         ret = factory(shortcut)