Custom Form – Random System Icons Appearing on Lists

The following icons appear at the top of a form from a list of SharePoint 2013 sites on-premises. The use of the latest version of Internet Explorer 11 but also in other web browsers such as Firefox. The shape seems well below the red line. This only happens for two users (which I know up to now), and only on the occasion. An F5 erases the icons and the shape looks normal. When users enter edit mode, they sometimes get an empty screen and an F5 clears the problem again.

We have a custom InfoPath form on this list and I have tried to republish it.

It has been running for about two years and suddenly, it started to happen about two weeks ago, and again for only two users. We have solved all the usual problems encountered with these users, including rebooting the machine, removing the cache, resetting IE ……

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