Mozilla Thunderbird is a standalone mail and newsgroup client. This update upgrades Thunderbird to version 52.3.0. Security Fix: * Multiple flaws were found in the processing of malformed web content. A web page containing malicious content could cause Thunderbird to crash or, potentially, execute arbitrary code with the privileges of the user running Thunderbird. Red Hat would like to thank the Mozilla project for reporting these issues. Upstream acknowledges Mozilla developers and community, Looben Yang, Nils, SkyLined, Oliver Wagner, Fraser Tweedale, Mathias Karlsson, Jose Maria Acuna, and Rhys Enniks as the original reporters.