If a malicious site uses the "view-source:" protocol in a series within a single hyperlink, it can trigger a non-exploitable browser crash when the hyperlink is selected. This was fixed by no longer making "view-source:" linkable. This vulnerability affects Firefox < 52 and Thunderbird < 52.
A potential memory corruption and crash when using Skia content when drawing content outside of the bounds of a clipping region. This vulnerability affects Thunderbird < 52.1, Firefox ESR < 52.1, and Firefox < 53.