After 3 minutes, this just crashed the browser on an old AOSP stock Android device I have. The last time I implemented something like this as a proof-of-work (f

After 3 minutes, this just crashed the browser on an old AOSP stock Android device I have. The last time I implemented something like this as a proof-of-work (first party) solution, it fell apart instantly when someone wrote a dedicated bot for it - 5 zeroes were found in sub-0.5s times in non-browser-JS.