Issue Summary

The Slack / MS teams integration App integration pages on manage portal are intermittently crashing and not rendering, specifically for pages with 400+ channels configured. 

Steps to Reproduce

1. Go to Manage -> Apps -> Slack / MS teams
2. Configure Slack / MS teams integrations using https://support.atlassian.com/statuspage/docs/set-up-a-slack-integration/ or https://support.atlassian.com/statuspage/docs/set-up-microsoft-teams-integration/ 

Expected Results

The integrations should work as expected and as mentioned in the support documentation above.

Actual Results

If a page has a lot of channels configured for the integrations (currently we are facing the intermittent failures for about 400+ channels configured), the Manage portal app pages do not load as expected, and incident updates intermittently fail to be posted to Slack / MS teams channels.

Workaround

Currently there is no known workaround for this behavior, except for configuring a lesser number of slack channels per page. A workaround will be added here when available