It was the safe_sleep function. Here's an issue on it [0]. IIRC there was an early issue, but really this is code that never should have made it in. Here's the conditional in question

  SECONDS=0
  while [[ $SECONDS -lt $1 ]]; do
      :
  done

Here's the fix... (s/!=/-lt)

  while [[ $SECONDS -lt $1 ]];

It's a fallback sleep function for if you don't have the sleep command, (or read, or ping) then it'll increment SECONDS (special variable) until the time has passed because : does nothing (it will peg your CPU though).

Problem is the loop isn't computed with infinite precision. Doesn't take a genius to figure out < is infinitely better than != here and you'd be right to guess that people did in fact waste thousands of dollars getting stuck in infinite loops that were entirely unavoidable.

Here's the actual merge...[1]

At least it didn't take them months to merge this line, which should have existed from day 1 too (a very very well known pattern for writing bash scripts)[2]

[0] https://github.com/actions/runner/issues/3792

[1] https://github.com/actions/runner/pull/3157/changes

[2] https://github.com/meshtastic/firmware/pull/7922

FYI, in your reproduction, both of the conditionals are the same. But you are right, the initial implementation was `!=`

    while [[ $SECONDS != $1 ]]; do

became

    while [[ $SECONDS -lt $1 ]]; do

>.< idk why I copy pasted my line with the correction again. Sorry about that, but glad you got it despite that haha