It appears that in 8.16.0, the UX to add connectors to a rule has changed, and it appears to not list existing Slack API connectors as potential actions.
I was able to repro this in the QA Overview cluster, by creating a new ES Query rule, and trying to add the Slack API connector named o11y-alertbot. It's not available in the new list, only Slack is listed in the new connector type list on the left of popup, Slack API is not, and the o11y-alertbot is not listed under Slack either (in case both types were being combined together in the list).
It appears that in 8.16.0, the UX to add connectors to a rule has changed, and it appears to not list existing Slack API connectors as potential actions.
I was able to repro this in the QA Overview cluster, by creating a new ES Query rule, and trying to add the Slack API connector named
o11y-alertbot
. It's not available in the new list, only Slack is listed in the new connector type list on the left of popup, Slack API is not, and theo11y-alertbot
is not listed under Slack either (in case both types were being combined together in the list).