That is interesting as I always want the download window somewhere so I know how the download is progressing and when it's finished. All browsers I use default to the Download window showing.
What I was trying to say was it seems to be pretty standard behavior with all major browsers out there. With Safari I have a feeling all you can do is what you are doing with Glims.
I will look around and see if I can find anything else that does what you are after.
If the problem is with it opening in front of the page you're viewing, you can move the downloads window off to the side while it's open and it will remember that position. Have mine set in glims to close after 3 seconds of inactivity which makes it almost invisible to me. I have switched up to using my browser at about 2/3 screen. If you're still in the habit of using your browser in full screen this won't help much.
The other option after it opens, just a single click on the browser window wherever your cursor happens to be instead of closing the downloads window. That'll force it into the background and let glims close it when the download is finished.
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