In addition, a filter on displaying private messages in a similar manner would also be useful…
`add_filter( ‘bp_get_activity_content_body’, ‘bbp_whitelist_do_shortcode’ );`
Needs to be:
`add_filter( ‘bp_get_activity_content_body’, ‘bbp_whitelist_do_shortcode’, 1 );`
Apparently something else on the same filter was stripping shortcodes and their contents out of the activity body BEFORE this filter was being applied, so I just had to give it a high priority to work.
Also I found the other hook I was looking for, so I can apply the shortcodes to private messages. It turned out I can use `bp_get_the_thread_message_content` for that.