Appears to be outputting Debugging Information at start of html

A client has this plugin on their site. Since the most recent update it appears to be causing Debugging Information to be output before the site html.

Deactivating the plugin removes the Debugging Info text.

A quick search on Google (for: ‘Debugging Information: Login Time: 1440 Salt:’) and I can see a bunch of other sites with the exact same issue, all with Front End Users installed.

Can you take a look and advise please?

Many thanks.

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