As of version 3.7.3, Zanata does not allow to add a comment for an entry without translation.
There is a case where a translator wants to leave a comment even when an entry has no translation.
For example, for a case where an original string is difficult to translation, a translator wants to leave a comment about why it is not/cannot be translated now, or a comment that this is being fixed in an upstream project (see bug XXXX).
I believe it is useful to allow a translator to add a comment even when an entry has no translation.
I am using version 3.7.3 (Zanata OpenStack instance).
I don't believe this has ever been possible, but I just wanted to clarify that with you.
We are focusing on the new editor, so I will add this to the list of consideration for implementation.
Do we have any metrics/idea of how useful the chat window is? If the comments system is greatly improved for the new editor, (eg this report, and being able to "tag" people) we may not need chat at all.
No metrics afaik, but I don't think chat really adds anything. It would be more in line with use cases for there to be commenting functionality for the workspace and/or for each string to be translated. I will look into this.