Issue when browsing backoffice "Cannot read property 'parent' of null"

Hi everyone,

We are using hybris 6.1.0.4 and we are facing issues when browsing the backoffice (specially with products). It happens from time to time, when hovering over a product image, or when trying to add new item to a collection. It forces us to refresh the browser and then it works until next time it happens. The error itself is this one, the logs don't say anything else.

Is this a known issue? How can we solve this?