problem using different Chinese language settings

problem using different Chinese language settings

I recently upgraded to JS 4.9.2 after joomla upgrade to 3.4.1 . my shop requires I use en-GB , zh-CN and zh-TW . previous version I could set separate language tab for each. the zh-cn and zh-tw both showed the same flag (cn flag shows - tw flag did not show in JS, but correct flags show in joomla language selector) BUT the fields in each tab could show the correct text input. so once I know which show which, I could put traditional text in fields under one tab, simplified in fields in the other and text would display correctly. IN new version, the two CN languages show with different tab (check pic), same flag, but save changes to one tab over writes the characters and setting of the other tab.( if I set 1 alias to prod-cn and save, then move to next cn tab and put alias as prod-tw then save, when return to first tab prod-cn is changed to prod-tw. same for all name and text description). save one tab, move to other change and save, changes over write on the other tab. en-GB does not change. other language settings in joomla seem no problem. Is there a config file I can edit to allow JS to recognize the changes in the language so that zh-cn and zh-tw are not same? tks for your help

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