I would say uptime and UX/UI:

uptime:

Incomplete pull request results in repositoriesSubscribe Update - We are actively reindexing the remaining ElasticSearch indexes. Our priority is ensuring correctness and avoiding further impact. We are taking a measured approach to safely backfill data and will share additional updates as progress continues. Apr 28, 2026 - 15:58 UTC Update - After yesterday’s incident, we are investigating cases where /pulls and /repo/pulls pages are not showing all indexed pull requests. This is because our Elasticsearch cluster does not currently contain all indexed documents.

No pull request data has been lost. As pull requests are updated, they will be reindexed. We are also working on accelerating a full reindex so these pages return complete results again. Apr 28, 2026 - 14:51 UTC Investigating - We are investigating reports of degraded performance for Pull Requests Apr 28, 2026 - 14:17 UTC