Keeping tabs of what the admins do...

You should be able to get the name of the moderator with [name]. As for the name of the user who created the post you might be able to use the built in nesting feature for that. Specifically the below might work.

[cb:userdata field="name" user="[var3_user_id]" /]

With activity_onBeforeUpdateStreamActivity the updated activity entry is in var3 and the old entry is in var4. So you should be able to get the activity messages as follows.

Edited Message: [var3_message]
Old Message: [var4_message]

Works like a charm now. But be aware... Groupjive group moderators are NOT in the category of ALL MODERATORS (at least that is what my tests showed.) so I have simply set the AA to EVERYONE.
Those that change their own message are anyway filtered out by the Condition.
The Load By I have set to NONE to produce a new activity everytime someone edits something otherwise the old message gets lost.
Also, I have set the Asset of the new post to be activity.[var3_user_id].editlog. The reason is that I will make an Activity module with asset activity.[self].editlog + comment.[self].editlog.

That way people can check if their own posts got modified and have everything in black and white. Also, since there is another user who is owner of the activity that they are getting shown, they cannot edit it and then complain/sue someone saying that they did that, wrote that etc...

That would have been good to have it as a System Auto Action btw...

Unfortunately there seems to be a bug in the translation part. I have made you a video here to show it as it would be Possibly to difficult to explain. 1drv.ms/v/s!Ap2Qzya9x1hVj-o960h4DrTbF2FNGQ?e=FXaXka

I don't recommend storing activity for that. You'll bloat the activity table with information irrelevant to everyone except admins. I suggest just storing that information to Joomlas action log database then you can view it in Users > User Actions Log and reference it if needed.

Future release of CB Activity will just keep better track of edits and actually provide access to the full edit log in a separate database table. Added a feature ticket for this so I don't forget.

forge.joomlapolis.com/issues/8364

Unfortunately there seems to be a bug in the translation part. I have made you a video here to show it as it would be Possibly to difficult to explain. 1drv.ms/v/s!Ap2Qzya9x1hVj-o960h4DrTbF2FNGQ?e=FXaXka

There is no language string for "has edited the comment of". Is that a custom activity title you're using? Please use a language key instead. Example as follows.

Title: HAS_EDITED_COMMENT_OF

Key: HAS_EDITED_COMMENT_OF
Text: has edited the comment of

I don't see what this would have to do with the new language overrides behavior and more to do with the language text as a key you're using isn't being found.

Please keep in mind in the future you will -have- to use language keys. We will likely be enforcing this in CB 3.x.

Hi, have you ever admined an FB group in Vietnam? they are harpies over there. If you even touch the slightest bit their posts, they are going to come over and kill you if they do not have an exact protocol of what changes have been done (so not only relevant to admins) .

Anyway, with the Group creators and the moderators being admins, I found it better to show a "change log" to each user with what has been changed by the administrators in their own post. It concerns everyone, especially with the GDPR (you are always the owner of your own information) and the soon to be upcoming legislation about Social networks being responsible for reacting to complaints etc...