I decide how I use my phone vs my phone decides how I use it

Has anybody an idea how to get the thumbnails to work properly?

I the post here it says once using the 'Upload Image' function, that the image will show in the post and as thumbnail. The latter doesn't seem to work for me on Jerboa.

The only way that worked for me so far was to link the uploaded image (via the button) by adding the url as ![](IMAGE_URL) to the body of the post.