Tags have started looking weird on Slack messages

Messages used to come through to Slack something like this:

MyApp - error still occurring 1 minute later - 
undefined method `request_uri' for #<URI::Generic:0x000000108376c8>
Did you mean? require
Tags
----------------
tag01, tag02, tag03

But recently they have started coming through like this:

MyApp - error still occurring 1 minute later - 
undefined method `request_uri' for #<URI::Generic:0x000000108376c8>
Did you mean? require
Tags
----------------
Tags
----------------
https://app.raygun.com/crashreporting/myapp?filterBy=Tag?tag01, https://app.raygun.com/crashreporting/myapp?
filterBy=Tag?tag02, https://app.raygun.com/crashreporting/myapp?filterBy=Tag?tag03

Presumably either a Raygun or Slack update sometime in July.

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Problem appears to be resolved as of today.

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