I can't find Telegram notfication on Sentry > settings > Integrations ?
Same strory
Where should I run pip install sentry-telegram?
There are many of sentry's containers
UPD
it showed when I run docker exec sentry_onpremise_web_1 pip install sentry-telegram && service sentry restart

But I dont use any docker in my project
By the way, could please anyone explain to me why the plugin is marked with "Not Installed" label, while it's obviously installed?
If you come here in 2023, I had to run the command as follow:
docker compose exec web pip install sentry-telegram && docker compose restart web
Or with sudo in case your docker needs it
sudo docker compose exec web pip install sentry-telegram && sudo docker compose restart web
You can also try with the old docker-compose if docker compose doesn't work for you