Why do bookmark folders open when you drop a bookmark on them?

When I'm cleaning up my bookmarks, I've set up topic folders to drop bookmarks in.

Every time I do, the folder opens a show the contents, and stays open.

This open folder creates a whole long list that forces the user to either click to close, or scroll down past all the contents to get to the other folders.

Is there no work around to simply let users drag and drop without opening the folder. Sorry but Chrome does this.