Repro steps (macOS only):

1. Start Unity with no floating windows open
2. Switch to the default layout, with the Project view open
3. Press the green button to put Unity into fullscreen mode
4. Select Windows->Analysis->Profiler in the menu bar. Note that in this case, the floating window will stay on top of the full-screen main window.
5. Change the profiler mode to "Editor" and record a few frames.
6. Select a frame from the "highlights" view (topmost row usually)
7. Line up the highlights view in the bottom pane so it partialy overlaps the edit box of the main editor's project window
8. Select the main window and click in the search box of the projects window. Now slowly move the mouse cursor to the left over the highlights view in the unfocused floating window

Actual behavior: Itermittently the cursor will change to the I-beam when it should be an arrow. It looks like macOS is selecting the rect from the cursor under the window. However, if you slowly drag left past when the project view search box has ended, it remains an I-beam.

Expected behavior: The cursor should be an arrow since the project view search box we are over is obscured by the profiler window