I use RStudio IDE with three panes:
- on the right top: environment, files, git etc.
- on the right bottom: the console
- on the left side (extended): the editor
However, I cannot totally remove the fourth, left bottom, pane (generally it's the 'Viewer' pane). That fourth pane pops up when you plot something, or close all files in the editor, re-initialize the RStudio etc. That's a bit annoying.
Actually, there's an issue reported about this some time ago: