While running on my AWS box since earlier in the week, my 10-parallel test/format job hit an assertion after over 1800 iterations (i.e. over 18000 jobs):

[1583975124:400425][16980:0x7ffa42ffd700], t, file:wt.wt, WT_CURSOR.next: __wt_ovfl_read, 78: i < track->remove_next

Given how long it had been running, on changeset 9ea89ea5, I expect it will be difficult to reproduce. I will save a copy of the directory to save the core file.