If Chosen is applied to a select element that's part of a collapsed fieldset, the layout is incorrect when the fieldset gets expanded.
If the parent fieldset is expanded by default, all works fine. See screenshot.
Looks like this is the related issue on github for the chosen plugin:https://github.com/harvesthq/chosen/pull/444
Can you check if it works for you with the latest dev version ?
For me it seems to work now, could be because of the new min-width setting...
This should be working by now, if not please reopen.
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