Current this works (with #1831524: Previous/Next revision does not show diffs → ), but the integration is bad, with the context jumping from the Diff modules page callbacks and the Workflow Moderation page callbacks.
Patch coming.
Closed: outdated
3.0
Code
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It's likely this issue predates Contrib.social: some issue and comment data are missing.
Given the proximity of EOL for Drupal 7, marking this as won't fix. The likely final Drupal 7 release of diff has landed in https://www.drupal.org/project/diff/releases/7.x-3.5 → . If this is something still applicable to a more modern version of the module, feel free to re-open and post additional notes.