It’s possible that there’s a conflict on your site. Could you please try to reproduce the issue on one of the WordPress’ stock themes (like Twenty Sixteen) with other plugins deactivated? If it disappears, then you can activate the theme and plugins one by one to see which one causes the issue. If you use a cache plugin, could you please clear the cache on your site first? If that doesn’t work, could you please open a new ticket too?
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