This is a very, very long test form with 3K pop-up/drop-down inputs. It doesn’t do anything. It is just used to test the browsers for potential overflow conditions when trying to render extremely long forms and see which browsers/versions can render the page and which will hang/time-out.

Obviously, this is not what any typical form would or should look like. I encountered the bug on a very large WordPress multi-site network with over 5K sub-sites. One of the plugins we use constructs a form on the fly with one pop-up/drop-down input for each blog. It started hanging Chrome (and Edge which is also based on Chromium). FireFox, Safari and older versions of Chrome worked fine. Because the plugin was in the backend of a live site I created this test page to help backtest and isolate exactly which version of Chrome introduced the bug that causes such large forms to hang, so that I could report the bug and get it fixed by Google.

Results of Initial Testing on Mac OS X (Sierra at the time)

  • Brave 1.33.106 based on Chromium 96.0.4664.110 hangs
  • FireFox 95.0.1 (64-bit) works
  • Safari Version 12.1.2 (12607.3.10) works
  • Dissenter 0.70.122 based on Chromium 78.0.3904.87 works

Results of Backtesting Earlier Versions of Chrome/Chromium to Isolate Where it Broke

  • Chromium Version 90.0.4430.0 (Developer Build) (x86_64) Goes through 9 waits and eventually draws in about 2:52.
  • Chromium Version 91.0.4472.0 (Developer Build) (x86_64) Goes through 6 waits and eventually draws in about 2:50.
  • Chromium Version 92.0.4515.0 (Developer Build) (x86_64) Goes through 6 waits and then hangs with Aw, Snap! Error code: 5 after about 2:23.
  • Chromium Version 93.0.4577.0 (Developer Build) (x86_64) hangs with Aw, Snap! Error code: 5 after about 2:10.

So, it looks like it broke on Chrome/Chromium version 92 and later. None of those versions can draw the page, where all versions of FireFox can draw the page with no problems.