Electron: Cross-origin iframe can position native autofill popup

Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to 39.8.8, 40.9.0, 41.2.1, and 42.0.0-beta.3, the native autofill popup could be positioned by a cross-origin iframe outside that iframe's bounds, over the embedding page's UI, enabling clickjacking or spoofing of trusted UI. Apps are only affected if they embed untrusted content in iframes within windows that also display trusted UI. Apps that do not embed untrusted third-party content are not affected. This issue is fixed in versions 39.8.8, 40.9.0, 41.2.1, and 42.0.0-beta.3.