Multiple uploads in main attachment populates Files

1. create a File document
2. drag and drop a file named test1.xls as main content
3. observe there are nothing in files and only the main content added
4. click on Files tab
5. click on Summary tab
6. drag and drop a second file test2.xls as main content (see screenshots)
7. observe the file test1.xls has been replaced with test2.xls in the main content section (expected behavior) but it has also been added in the Files section (this should not happen).

Note: this does not happen when remaining in the Summary tab. The tab change seems to trigger the issue.