Due to trashed page having the slug that will normally have been assigned to the new page. about. the new page gets the slug of. about-2. resulting in URL being http yoursite about-2..
The time it fails to do so is if new page or post has claimed the original slug in.
overview of the approach employed by the plugin to resolve the number of slugs potentially conflicting with posts in the trash..
In order to understand the crux of the terms refresher unique slug handling WP.
The safe slug differ from the need slug if any present post like trashed post has that slug or less possible is disabled for permalink reasons such as feeds or date archives..
When the two slugs don't match it has to determine if the conflict is due to trashed post or not so it attempts to find trashed post with the need slug..
If no such trashed post is locate the conflict is with live post or was unsafe slug so the safe slug will be used by the new post so again nothing needs to be done..
In order to be able to restore trashed post to its original slug the original slug is includes in postmeta...
For post transitioning away from the 'trash post status recheck to see if its slug was corrected highlight by the presence of the postmeta field only assigned if the original slug was changed due to conflict while the post was in the trash..
In case the postmeta field for the original slug value gets free since the also untrashed post is exposed in some fashion with its current slug and will abide by it going forward.....
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