When are the prescribed incantations (adhkar) recited after the obligatory prayer if there is no time interval between the post-prayer supererogatory (Sunnah) prayer and the Tarawih prayer in the mosque?

The default is to perform the remembrances (dhikr) after the prayer and before the post-prayer Sunnah (supererogatory prayer). This is indicated by numerous prophetic hadiths, which state that the dhikr is recited upon completing the prayer. A slight delay or forgetting does not invalidate it. Some jurists have preferred performing the post-prayer Sunnah before the remembrances, but the opinion of the majority is clearer and more preponderant. If the mosque attendees perform the Sunnah immediately after the obligatory prayer, and then the Tarawih prayer, one can perform the remembrances and delay the Sunnah until after the Tarawih, or perform the Sunnah after a short interlude of seeking forgiveness (istighfar), then perform the remembrances between or after the Tarawih, or shorten the remembrances and the Sunnah to combine the virtues.