Yeah, I know what you mean. I wish Adobe would give more control over hiding elements of the interface.
I was playing around with Google Drive in Chrome on my Mac and I was able to achieve this. The following is a whole-screen screenshot without anything cropped.
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Steps (using Google Chrome, on a Mac): I open new Google Chrome window, so it has only one tab. I move the Chrome window to its own space (drag and hold at the right-edge of my screen). I open the PDF in Google Drive. I right-click on the tab and select "Duplicate" from the context menu. From the menu bar I click on "Window" and select "Tile to the Right of Screen". Works well, except the google PDF control will appear and disappear based on your mouse cursor movements. But I can't figure out what is actually triggering the tools to appear and disappear. If I could more reliably bring them up when I wanted them and hide them when I didn't, this would be perfect.
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