Multiple Attachment Macros via Excerpt-In Macro don't work with Drag & Drop

I created a Page (named overview) and three childpages. On every child page there is an excerpt macro with an attachment macro inside.

On the overview page, I included all three excerpts from the childpages, so I get 3 attachment areas on one page.

If I click on the upload function in one of these macros the file will be uploaded to the childpage. That's what I want. But if I drag & drop a file into one of the three attachment areas, the file will be uploaded to the overview page instead.