No picture zoom in Twidere app

When I use Twidere app (a free Twitter app) I can’t zoom in (nor out) pictures. When I open the picture in any browser it works.
It is not quite the same error that is mentioned in https://forum.fairphone.com/t/fp2-zoom-with-built-in-picture-viewer-broken/12952

In my case most pictures are shown too small. On my old phone (OnePlus One) Twidere worked fine.

Any hints or workarounds for this?

I use the google-free OS. (built on 27.01.2015)

Maybe this issue is not correctly fixed?

I haven’t had this issue in two years using Twidere until I switched to the FP2.
But writing the programmer may also help.