# What this PR does
Currently, when a user gets mentioned in an alert group thread and the
user is not in the Slack channel, the Slack bot sends the following to
the channel:
> ⚠️ Tried to ask USER to look at incident. Unfortunately USER is
not in this channel. Please, invite.
This PR changes this behaviour to instead send a direct message to the
user. The message contains a link to the main alert group message in
Slack.
<img width="806" alt="Screenshot 2023-01-17 at 19 25 36"
src="https://user-images.githubusercontent.com/20116910/212996457-02db183f-2041-4998-b743-bd5b6c84b7b5.png">
## Checklist
- [ ] Tests updated (N/A)
- [ ] Documentation added (N/A)
- [x] `CHANGELOG.md` updated
c93ee5c554
