Post Meta Edit Lock: The “Post Meta Edit Lock” are flags in the “wp_post_meta” database table, no “wp_post” table.
When you edit a post, old or new, WordPress creates 2 records in post meta table for warn other editors that someone is in edit.
So, these records can remain on server for a very long time. When a Blog has many posts, for example 100, in post meta table you can found 200 “dead” records.
Delete these records is not dangerous.
But if you remove “Post Meta Edit Lock” It don´t cause damage with the Google index, in SEO term.
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