See https://bugzilla.mozilla.org/show_bug.cgi?id=1673345#c0 for more context.

If the executeScript query fails due to an AbortError, we will assume the command was successful and will silently return null. The goal of this bug is to try to better track the completion of the command so that we can decide if it needs to be retried with the next JSWindowActor pair.

Note that in this weeks TPAC sessions this will be discussed. I will update the bug later this week.

(In reply to Henrik Skupin (:whimboo) [⌚️UTC+2] from comment #1)

Note that in this weeks TPAC sessions this will be discussed. I will update the bug later this week.

Looks like I forgot to update the bug. The meeting notes regarding this topic can be found at:
https://www.w3.org/2020/10/27-webdriver-minutes.html#t05

Given the notes we should raise an error in case of both commands but it looks like that we would need a WebDriver classic spec update first.

James, I assume it should be handled similar to suddenly appearing user prompts and erroring out with a javascript error?

Yes, that seems correct. I think ECMAScript just basically says "agents can stop making forward progress", so we might need to add some text to WebDriver to handle this explicitly.

https://github.com/w3c/webdriver/issues/1708