diff --git a/debian/changelog b/debian/changelog
index 7b73467f..df8648c5 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,10 +1,18 @@
 livecd-rootfs (2.525.20) UNRELEASED; urgency=medium
 
+  [ Steve Langasek ]
   * Drop /etc/update-motd.d/51-cloudguest from cloud images; this is not
     consistent with current Ubuntu Advantage product language.  Any future
     customizations to update-motd for cloud images should be done via a
     package instead.
 
+  [ Julian Andres Klode ]
+  * Minimize the number of manually installed packages in images by marking
+    dependencies of metapackages as automatically installed. (LP: #1800610);
+    but do not mark direct dependencies of ubiquity as auto installed. This
+    caused cryptsetup to remain auto on the installed system in bionic (see
+    LP #1801629)
+
  -- Steve Langasek <steve.langasek@ubuntu.com>  Tue, 12 Mar 2019 11:39:34 -0700
 
 livecd-rootfs (2.525.19) bionic; urgency=medium
diff --git a/debian/control b/debian/control
index 92378a3e..f7f315de 100644
--- a/debian/control
+++ b/debian/control
@@ -28,6 +28,7 @@ Depends: ${misc:Depends},
          parted,
          procps,
          python-minimal | python,
+         python3-apt,
          python3-software-properties,
          qemu-utils,
          rsync,
diff --git a/debian/install b/debian/install
index 91d6ea37..4eb70070 100644
--- a/debian/install
+++ b/debian/install
@@ -1,2 +1,3 @@
 live-build usr/share/livecd-rootfs
 get-ppa-fingerprint usr/share/livecd-rootfs
+minimize-manual usr/share/livecd-rootfs
diff --git a/live-build/auto/build b/live-build/auto/build
index 1912ab5b..aa30f55a 100755
--- a/live-build/auto/build
+++ b/live-build/auto/build
@@ -435,6 +435,8 @@ EOF
 	(cd chroot && find usr/share/doc -maxdepth 1 -type d | xargs du -s | sort -nr)
 	echo END docdirs
 
+	/usr/share/livecd-rootfs/minimize-manual chroot
+
 	lb binary "$@"
 	touch binary.success
 ) 2>&1 | tee binary.log
diff --git a/minimize-manual b/minimize-manual
new file mode 100755
index 00000000..c8e3c166
--- /dev/null
+++ b/minimize-manual
@@ -0,0 +1,63 @@
+#!/usr/bin/python3
+"""Minimize the number of manually installed packages in the image.
+
+Finds all manually installed meta packages, and marks their dependencies
+as automatically installed.
+"""
+import sys
+
+import apt
+
+
+def is_root(pkg):
+    """Check if the package is a root package (manually inst. meta)"""
+    return (pkg.is_installed and
+            not pkg.is_auto_installed and
+            (pkg.section == "metapackages" or
+             pkg.section.endswith("/metapackages")))
+
+
+def main():
+    """Main function"""
+    cache = apt.Cache(rootdir=sys.argv[1] if len(sys.argv) > 1 else None)
+    roots = set(pkg for pkg in cache if is_root(pkg))
+    workset = set(roots)
+    seen = set()
+    ubiquity_depends = set()
+
+    with cache.actiongroup():
+        while True:
+            print("Iteration", file=sys.stderr)
+            to_proc = workset - seen
+            if not to_proc:
+                break
+            for pkg in sorted(to_proc):
+                print("    Visiting", pkg, file=sys.stderr)
+
+                if pkg not in roots and pkg not in ubiquity_depends:
+                    pkg.mark_auto()
+
+                for dep in (pkg.installed.dependencies +
+                            pkg.installed.recommends):
+                    for bdep in dep.or_dependencies:
+                        for ver in bdep.target_versions:
+                            if ver.package.is_installed:
+                                if pkg.name == "ubiquity":
+                                    ubiquity_depends.add(ver.package)
+                                if pkg.name != "ubiquity":
+                                    # Reprocess this package again, as we did not mark it when we visited it from ubiquity
+                                    try:
+                                        ubiquity_depends.remove(ver.package)
+                                        # This will raise the KeyError here if ubiquity did not depend on it
+                                        seen.remove(ver.package)
+                                    except KeyError:
+                                        pass
+                                workset.add(ver.package)
+
+                seen.add(pkg)
+
+        cache.commit()
+
+
+if __name__ == '__main__':
+    main()