We are currently sending Java exceptions to the Sentry backend by using raven.captureException instead of raven.captureMessage:
 

if (data.log.exception) {
  this.raven.captureException(new Error(data.log.message), errorData);
} else {
  this.raven.captureMessage(data.log.message, errorData);
}

This makes Sentry aggregate litterally all logs that have an exceptions associated into a single event. This is because doing the new Error(... we create an exception from the place it is, and it's always the same. So Sentry somewhat rightly sees those as the same.

And unfortunately, given we had marked as ignored the "SmokeTestException" one, everything got ignored the same way until recently as I was looking for that specific SmokeTestException ignored on purpose. And only by chance I finally saw in the Events tab that many unrelated events were merged there... :facepalm:

Example:
The title of the Sentry issue:

and the Events tab:

Expected behavior

Exceptions should be sent like the rest. Using the message as the title, and the exception can stay as is currently.