Great.
I hope it will be a acp option which can be used for own options too, because i wanted to suggest something similar:
There are several acp places , where i have ATM 1 option => (node chooser)
BUT since 1.1 we can also define thread prefixes, so it would be better to have automatic a option for both=>
Choose Forum (= nodechooser)
once you selected the forum, the second select option get upgraded via ajax and includes all thread prefixes which can be used in the node....
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