Profile pictures and some embedded images are strange colours

Symptoms

After upgrade to 6.2.2, some profile pictures are strange colours. This issue only affects jpgs that were uploaded around 2+ years ago, when avatars were stored with their filenames in the attachment table rather than simply 'user-avatar'.

Images that are ok are served as src="/download/attachments/425988/user-avatar"
The ones in negative are served as src="/download/attachments/8782333/{file-name}.jpg"

Inverse colours:

Correct colours:

If you append ?effects=blur to the end of the URL you get the correct colours back, therefore this appears to be related to the image rotation work done in 6.2.2.

Workarounds

1. Go to <your-confluence-url>/admin/darkfeatures.action and add imageFilter.exif.rotate.disabled. This will disable the image rotation work done for CONFSERVER-32762, but it will resolve this display issue. Be sure to remove it once this issue is resolved.
2. Individual users can upload a new profile picture (jpg, gif or png will all work)

Resolution

If you upgraded to 6.2.2 and are experiencing this issue, you need to perform an additional step to resolve it:

1. Upgrade to 6.2.3
2. For Confluence Server:
   • Delete the contents of <confluence-home>/imgEffects
3. For Confluence Data Center:
   • Delete the contents of <confluence-shared-home>/imgEffects