Yeah I was just looking for this old script last night and just found it :)
https://gist.github.com/ormaaj/04923e11e8bdc27688ad If you scroll down to the output for "test 3" where "h" gets called and passes a local "x" to a function that creates a reference to it and exports the reference you can see that bash calls "x" unset in both the first and second scope. As I recall we were discussing the way exported locals interact between scopes at the time, not namerefs, but I added the case for namerefs since I wasn't sure how this should work. I should probably run it again with the current devel branch. Even though bash doesn't yet support references for parameters like ksh93, neither does mksh, which also shows differences from bash.