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Can you please look at JS Activity Stream module since it does not display all profile activities when Profile streams option is selected. Works OK in case of Group and Event options.
Also, can you introduce option to enable loading more activities on scroll?
You commented that the JS Activity Stream module uses the "old" template with Send button. I have the same problem - except that the "Send" button doesn't do anything. Did you get a solution to this problem?
On default JomSocial 4.5 there is no Send button, and Enter key is used to make comment on content. Something is messing that function on your side so activate Admin/Mod or create new post for that issue.