Hi Ingo,
That's a retainer on the left side of the Taptic Engine. Somehow it got missed in our version of the Taptic Engine guide, but over at the Spanish site Nadie Me Llama Gallina their guide shows the clip after it's been removed.
[image|3085446]
It's on Step 11 of their "Vibrator" guide (it's in Spanish, but quite usable when put together with the Chrome auto translation).
[link|https://www.nadiemellamagallina.com/en/manuales/smartphones-1/apple-5/apple-iphone-se-2020-1217/placa-auxiliar-10827|Manuales / Apple iPhone SE 2020 / Auxiliary board|new_window=true]