Web platform tests take 60-80 minutes to run (about 10-20% of that is because the tab containing the tests is being closed after each test at present; that can likely be removed without compromising stability too much, but requires separate investigation) . It makes sense to break them into chunks. 3 chunks seems like a reasonable first guess for the right number.
Created attachment 8453143 [details] [diff] [review] 1036478.diff I have lost the ability to test this again. I'll see if I can find it again.
Comment on attachment 8453143 [details] [diff] [review] 1036478.diff lgtm, passes test-masters.sh.
looks like it was fixed