Affecting Defining non-configurable property on window will throw (currently only on Nightly and Developer Edition)

Published: | Categories: DOM


Firefox 42 and later will throw a TypeError when you attempt to define a non-configurable property on window with the Object.defineProperty or Object.defineProperties method. For now, this change has been made to Firefox Nightly and Developer Edition only. A couple of site compatibility issues have been found, and Mozilla developers are discussing the next step accordingly.