Editora 0.9.10. Archived, so links from that release keep working. Read the 0.16.0 page →
Window: Other (Editor / Tool Window)
window.other Cycle focus between the editor and tool windows.
How to run it
Open the command palette (M-x in the Emacs keymap) and search for Window: Other (Editor / Tool Window), then press Enter. It also has a default keybinding:
| Emacs | C-xo |