4 ms·

At this point I think that those APIs should be implemented with high-performance JS or Wasm and browsers should provide just enough API entry points to allow f

• chrismorgan 6y ago
  You could already do this by trawling the DOM and constructing whatever data structures you desire, and updating them by watching for modifications to the DOM with a MutationObserver. But performance would be somewhere between poor and execrable, and memory usage would skyrocket. Note also that this is doing batch updating, so you’ll be querying a potentially out-of-date DOM this way. I state confidently that there will never be a good way of doing this, because it fundamentally requires putting something that is unavoidably slow and memory-heavy onto the critical path (especially if you want it to operate synchronously rather than in asynchronous batch mode). No efficient implementation will ever be possible, given the design of the web.