This incident has been resolved.

The majority of our issues have cleared. We are waiting for Google's status on the issue to clear before resolving our own: https://status.cloud.google.com/incident/storage/20006

* if you're using sourcemaps, you're affected and may see bad stacktraces
* if you have uploaded debug information files, you're affected and may see bad stacktraces
* availability of event attachments may be affected

We have identified an issue with our cloud provider's object storage service that is preventing us from obtaining files necessary to complete event traceback processing and symbolification.

We have initiated a dialogue with their support team in efforts to mitigate the issue.