diff -Nru qtwebengine-opensource-src-5.12.8+dfsg/debian/changelog qtwebengine-opensource-src-5.12.8+dfsg/debian/changelog
--- qtwebengine-opensource-src-5.12.8+dfsg/debian/changelog	2020-04-10 08:15:12.000000000 +0000
+++ qtwebengine-opensource-src-5.12.8+dfsg/debian/changelog	2020-06-23 18:10:05.000000000 +0000
@@ -1,3 +1,9 @@
+qtwebengine-opensource-src (5.12.8+dfsg-0ubuntu1.1) focal; urgency=medium
+
+  * Backport upstream patch to fix live editing (LP: #1884550).
+
+ -- Dmitry Shachnev <mitya57@ubuntu.com>  Tue, 23 Jun 2020 21:10:05 +0300
+
 qtwebengine-opensource-src (5.12.8+dfsg-0ubuntu1) focal; urgency=medium
 
   * New upstream bugfix release.
diff -Nru qtwebengine-opensource-src-5.12.8+dfsg/debian/control qtwebengine-opensource-src-5.12.8+dfsg/debian/control
--- qtwebengine-opensource-src-5.12.8+dfsg/debian/control	2020-04-10 08:15:12.000000000 +0000
+++ qtwebengine-opensource-src-5.12.8+dfsg/debian/control	2020-06-23 18:08:19.000000000 +0000
@@ -1,5 +1,6 @@
 Source: qtwebengine-opensource-src
-Maintainer: Debian Qt/KDE Maintainers <debian-qt-kde@lists.debian.org>
+Maintainer: Ubuntu Developers <ubuntu-devel-discuss@lists.ubuntu.com>
+XSBC-Original-Maintainer: Debian Qt/KDE Maintainers <debian-qt-kde@lists.debian.org>
 Uploaders: Scarlett Moore <sgmoore@kde.org>,
            Sandro Knauß <hefee@debian.org>,
            Dmitry Shachnev <mitya57@debian.org>,
diff -Nru qtwebengine-opensource-src-5.12.8+dfsg/debian/patches/fix-live-editing.patch qtwebengine-opensource-src-5.12.8+dfsg/debian/patches/fix-live-editing.patch
--- qtwebengine-opensource-src-5.12.8+dfsg/debian/patches/fix-live-editing.patch	1970-01-01 00:00:00.000000000 +0000
+++ qtwebengine-opensource-src-5.12.8+dfsg/debian/patches/fix-live-editing.patch	2020-06-23 18:10:01.000000000 +0000
@@ -0,0 +1,18 @@
+Description: fix live editing
+ 4ceb67df8cd is cherry-pick 77->69 of f720be4 CVE-2020-6391,
+ unfortunately it breaks styled markup traverse by accidentally
+ inverting condition.
+Origin: upstream, https://code.qt.io/cgit/qt/qtwebengine-chromium.git/commit/?id=1417835f7de301a9
+Last-Update: 2020-06-23
+
+--- a/src/3rdparty/chromium/third_party/blink/renderer/core/editing/serializers/styled_markup_serializer.cc
++++ b/src/3rdparty/chromium/third_party/blink/renderer/core/editing/serializers/styled_markup_serializer.cc
+@@ -362,7 +362,7 @@ Node* StyledMarkupTraverser<Strategy>::T
+         continue;
+       }
+ 
+-      if (n->GetLayoutObject() || ShouldSerializeUnrenderedElement(*n)) {
++      if (!n->GetLayoutObject() && !ShouldSerializeUnrenderedElement(*n)) {
+         next = Strategy::NextSkippingChildren(*n);
+         // Don't skip over pastEnd.
+         if (past_end && Strategy::IsDescendantOf(*past_end, *n))
diff -Nru qtwebengine-opensource-src-5.12.8+dfsg/debian/patches/series qtwebengine-opensource-src-5.12.8+dfsg/debian/patches/series
--- qtwebengine-opensource-src-5.12.8+dfsg/debian/patches/series	2020-04-10 08:15:12.000000000 +0000
+++ qtwebengine-opensource-src-5.12.8+dfsg/debian/patches/series	2020-06-23 18:08:37.000000000 +0000
@@ -6,3 +6,4 @@
 verbose-gn-bootstrap.patch
 mipsel-linux-5.patch
 system-ninja.patch
+fix-live-editing.patch