well I think you are getting closer.
maybe they have a fix for it in the js in the alpha or beta version.
you could test a fresh install of vanilla 2.2b1, but I personally wouldn't use it on a live forum. and if it doesn't work try 2.2.101 purely as a test if it works ask them to port fix on 2.2b1 or 2.1
I wonder if it is something that is fixed in 2.2b1 or in 2.2.101
but I am not going to recommend it for a live forum as I am sure you are aware.
I may not provide the completed solution you might desire, but I do try to provide honest suggestions to help you solve your issue.
yes i am aware. but i'll try it out on a development and post the result here. Thanks for the follow up