Comment by hugs
5 days ago
i'm at the edge of my chrome internals knowledge here, but i'd answer the question with a question: isn't backendnodeid only stable within a single session?
that might not matter if the agent is re-finding the element between sessions anyway, but then you're paying a lookup cost (time + tokens) each time. compared to just using document.getelementbyid() on an explicit id.
iirc it's stable across sessions until the tab closes, even though their docs dont guarantee it.
we cant modify the dom to add IDs because we'd get detected by block-blockers very quickly. we're gradually trying to get rid of all DOM tampering entirely for that reason.