This update updates QtWebEngine to the 5.9.0 release. QtWebEngine 5.9.0 is part of the Qt 5.9.0 release, but only the QtWebEngine component is included in this update.

The update fixes the following security issues in QtWebEngine 5.8.0: CVE-2017-5006, CVE-2017-5007, CVE-2017-5008, CVE-2017-5009, CVE-2017-5010, CVE-2017-5011, CVE-2017-5012, CVE-2017-5013, CVE-2017-5014, CVE-2017-5015, CVE-2017-5016, CVE-2017-5017, CVE-2017-5018, CVE-2017-5019, CVE-2017-5020, CVE-2017-5021, CVE-2017-5022, CVE-2017-5023, CVE-2017-5024, CVE-2017-5025, CVE-2017-5026, CVE-2017-5027, CVE-2017-5029, CVE-2017-5032, CVE-2017-5033, CVE-2017-5034, CVE-2017-5036, CVE-2017-5039, CVE-2017-5040, CVE-2017-5044, CVE-2017-5045, CVE-2017-5046, CVE-2017-5052, CVE-2017-5053, CVE-2017-5055, CVE-2017-5057, CVE-2017-5058, CVE-2017-5059, CVE-2017-5060, CVE-2017-5061, CVE-2017-5062, CVE-2017-5065, CVE-2017-5066, CVE-2017-5067, CVE-2017-5068, and CVE-2017-5069.

Other important changes include:

• Based on Chromium 56.0.2924.122 with security fixes from Chromium up to version 58.0.3029.96. (5.8.0 was based on Chromium 53.0.2785.148 with security fixes from Chromium up to version 55.0.2883.75.)
• [QTBUG-54650, QTBUG-59922] Accessibility is now disabled by default on Linux, like it is in Chrome, due to poor options for enabling it conditionally and its heavy performance impact. Set the environment variable QTWEBENGINE_ENABLE_LINUX_ACCESSIBILITY to enable it again.
• [QTBUG-56531] Enabled filesystem: protocol handler.
• [QTBUG-57720] Optimized incremental scene-graph rendering in particular for software rendering.
• [QTBUG-60049] Enabled brotli support.
• Many bug fixes, see https://code.qt.io/cgit/qt/qtwebengine.git/tree/dist/changes-5.9.0?h=5.9 for details.

In addition, this build includes a fix for https://bugreports.qt.io/browse/QTBUG-61521 , a binary incompatibility in QtWebEngine 5.9.0 compared to 5.8.0.