Some Mail with white backgrounds are showing black instead of the system background color. <rdar://problem/52586836>
Created attachment 373544 [details] Patch
Comment on attachment 373544 [details] Patch Would be nice to test this.
Comment on attachment 373544 [details] Patch Clearing flags on attachment: 373544 Committed r247184: <https://trac.webkit.org/changeset/247184>
All reviewed patches have been landed. Closing bug.