When debugger stops on a breakpoint and I point on an array of objects a popup shows me arrows left to each object. Clicking on an arrow sometimes correctly expands the object and shows its content. Sometimes it doesn’t do anything, but when I move the cursor out of the popup so that it hides and then point on the array again it shows me the arrows I previously clicked on now pointing down but still doesn’t show the content/fields of the object/array-item. Sometimes it works… MacOS Ventura 13.2.1 (22D68) - but the same issue with previous OS versions, Firefox 110.0.1 (64-bit)
I just tried it in Firefox Developer 110.0b8 (64-bit). It works there (this time…)