Widget not showing in Chrome & Firefox

Hi,

I just recognized that the Popular Post Widget does not show any entries but the header only on chrome and firefox. Safari looks ok.

On Firefox & Chrome there is a JS-Error “Uncaught SyntaxError: unexpected token: ‘:'” referencing this line

"{"sampling_active":0,"sampling_rate":100,"ajax_url":"https:\/\/fosm.de\/wp-json\/wordpress-popular-posts\/v1\/popular-posts","ID":0,"token":"039cd14001","lang":0,"debug":0}"

Is there anything I can do about this error? Is this preventing chrome and firefox to show the posts?

Plugin Version: 5.2.4, WordPress: 5.5.3

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