Questions about "termination nesting level" and "ignore-opens-during-unload counter"

[annevk]

Are the only reason these are counters because they are used by both prompt to unload and unload?

Why is termination nesting level decreased sooner?

[annevk]

In particular it would be useful to have a distinct feature for just "prompt to unload" as the navigate algorithm tries to prevent itself from being invoked on an target browsing context's active document while prompt to unload is running. It currently does so without state and just some prose, which isn't great.

[domenic]

Are the only reason these are counters because they are used by both prompt to unload and unload?

I think these algorithms can be called recursively too e.g. by using window.close() during onbeforeunload.

Why is termination nesting level decreased sooner?

Not sure; perhaps observed behavior? It does seem like document.open() would be more weird to do during any of these stages, where e.g. window.alert() might be fine.

[annevk]

Not sure; perhaps observed behavior?

Unless any "unloading document cleanup steps" have side effects (I don't think that's supposed to be allowed) there doesn't seem to be a difference.

I was also wondering why termination nesting level was bound to the event loop. Currently event loop isn't tightly bound to something, so that seems like a questionable choice.