i am getting this error when creating a product using v9 community:

Uncaught Error: QWeb2 - template['FieldMany2ManyTag']: Runtime Error: TypeError: Cannot read property 'constructor' of undefined

http://104.236.237.202:8069/web/content/249-885d27a/web.assets_common.js:2444
Traceback:
Error: QWeb2 - template['FieldMany2ManyTag']: Runtime Error: TypeError: Cannot read property 'constructor' of undefined
    at Object.exception (http://104.236.237.202:8069/web/content/249-885d27a/web.assets_common.js:2444:7)
    at Engine.eval (eval at _render (http://104.236.237.202:8069/web/content/249-885d27a/web.assets_common.js:2478:73), <anonymous>:33:29)
    at Engine._render (http://104.236.237.202:8069/web/content/249-885d27a/web.assets_common.js:2477:296)
    at Engine.render (http://104.236.237.202:8069/web/content/249-885d27a/web.assets_common.js:2477:151)
    at OdooClass.render_tag (http://104.236.237.202:8069/web/content/438-2cd3716/web.assets_backend.js:3707:3650)
    at Object.handle_names (http://104.236.237.202:8069/web/content/438-2cd3716/web.assets_backend.js:3708:130)
    at fire (http://104.236.237.202:8069/web/content/249-885d27a/web.assets_common.js:644:299)
    at Object.fireWith [as resolveWith] (http://104.236.237.202:8069/web/content/249-885d27a/web.assets_common.js:649:198)
    at Object.deferred.(anonymous function) [as resolve] (http://104.236.237.202:8069/web/content/249-885d27a/web.assets_common.js:651:56)
    at http://104.236.237.202:8069/web/content/249-885d27a/web.assets_common.js:2721:271