Hello @Sanjay Jethva
Have you modified that js?
if not then copy your file from
https://github.com/magento/magento2/blob/2.1.6/lib/web/knockoutjs/knockout.js
please check your version, first copy into pub and then work then change it original position.a
After copy code make sure your new js load.
Hello @Sunil Patel,
Still its not working
If i set Enable WYSIWYG = No from Stores->Attribute->Product->meta_description attribute than this problem is resolved.
This is a temporary solution but seems like there is a problem with the WYSIWYG editor.
Thanks