I have a D8 site that's in development and I am getting this error thrown at random on pages which most of the time render quite happily. There doesn't seem to be any real pattern in it.
I can see that it looks like it's designed to prevent the renderer creating an infinite loop (the code is on line 133 of core/lib/Drupal/Core/Render/Renderer.php), but it isn't really clear what's actually causing it. The log error is pretty useless really.
Anyone seen this and found out the cause? Thanks