Arender has problems rendering

Customer reports glitchy rendering, which becomes evident when zooming images. It's intermittent, but becomes obvious after a few minutes of work.

Steps

• click "zoom in zone" icon, select an area of a document
• if document does not render properly (all elements must be visible), use zoom in/zoom out/full page until it does
• if document does not render properly after using zoom in/zoom out/full page, reload the page in the browser

Attached videos show the phenomenon. Attached assets can be used freely for reproduction outside of the customer environment.