Trakt's popular/trending charts are not including the tvdb in their API responses. It's unclear at this point in time if this is a mistake with their API that will be reverted or not.

In either cast, Trakt does include tmdb and imdb ids, when available, in their API responses.

The Trakt builders should not rely exclusively on the tvdb id, but fallback to the tmdb or imdb id when available. That'd make the software much more resilient and capable when Trakt's API responses are missing one or more of the external IDs.

References:

This conversation on Discord: https://discord.com/channels/822460010649878528/1440898378526363718

Discussion on Trakt forum: https://forums.trakt.tv/t/did-you-removed-the-tvdbid-value-from-api/87340

Trakt announcement of moving from tvdb to tmdb: https://github.com/trakt/trakt-api/discussions/250