YouTube search.list relatedToVideoId parameter stopped working on 7 August 2023
What changed
On 12 June 2023 the YouTube Data API revision history announced that the relatedToVideoId parameter of search.list would stop working on 7 August 2023, and removed a related videos example from the implementation guide. On 7 August 2023 the revision history records the parameter as removed from the documentation.
What it means
Any tool that built a related videos list with search.list and relatedToVideoId lost that feature.
Who is affected
Developers of tools that suggested related videos by calling search.list with relatedToVideoId. Marketers who only schedule uploads are not affected.
What to do by 7 Aug 2023
Remove calls that use relatedToVideoId. The deadline was 7 August 2023, so this should already be done.
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