Original Post from Ilya Grigorik: All Google+ widgets have been updated to use the script[async + defer] pattern! E.g. +1 button docs: http://bit.ly/YHoj96 What's the benefit? Loading widgets via script[async+defer] does not block the document parser (see [1]), and allows the preload scanner to discover the script resource and initiate an earlier fetch (see [2]). Net outcome, both your page and the widget load faster! Have a G+ widget on your page? Check out the docs for guidance on how to update your snippets. Kudos to the G+ team for taking the lead on this! Hope to see more widget providers adopt the same pattern. [1] https://developers.google.com/web... [2] https://www.igvita.com/2014... async-defer.png - mjc