Google says this is related to Skype's Click to Call add-on but there is a solution
Q I use Google Chrome and, on some web pages (such as Gmail), it has recently started displaying the message on the top of the browser: 'An additional plug-in is required to display some elements on this page'.
I click the option to allow the plug-in to install but nothing happens. I then click the ‘Problems installing?’ link and, again, nothing positive occurs. Can you please help me?
A This problem appears to be related to Skype's Click to Call add-on, as explained here. We’re not sure why the issue is occurring but the good news it that it has been acknowledged as a known problem by a Google support staff member (view the Google Chrome support thread here).
In the meantime, Google’s workaround is to disable the Click to Call add-on. To do this, click the spanner icon at the top right of the Chrome browser window, point to Tools and click Extensions. Now scroll down the list to find the Skype Click to Call entry. Click Remove, followed by Uninstall.
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