"Download directory" option downloads the whole project instead of the content of the currenct directory only

Within the last two versions (18.5.0-ce and 18.5.1-ce), the option "Download directory" inside the "Code" button downloads the whole project and not just the current directory.

This was tested using both docker images on the respective versions (tags) mentioned aheard, available from docker.io.

Previous versions prior to 18.3.x were working fine.