The third installment of the “batteries included” series dives into obscure yet practical features built into Emacs 28.1+. Author warns newcomers to master basics before exploring these tricks, which focus on stock functionality without external packages. Each tip promises a sub‑five‑minute learning curve, targeting veteran users who still miss low‑hanging shortcuts. Previous parts revealed undo‑in‑region and similar shortcuts, and this edition follows that approach.

One highlight enables dictionary-tooltip-mode, displaying word definitions as tooltips when hovering. With tooltip-mode already active, the feature pulls from local dictionaries or Wiktionary, covering contemporary jargon. Another tip shows that both find‑file (C‑x C‑f) and Dired accept wildcards, letting users open or batch‑delete files matching patterns directly from the interface. The wildcard syntax works in both interactive and scripted contexts.

Finally, the author recommends compare-windows, a lightweight command that lines up two buffers and reports the first mismatch from the current cursor positions. Compared with the myriad diff utilities bundled with Emacs, this function offers a quick, context‑agnostic glance at differences without launching a full diff suite. It exemplifies the series’ goal: surface hidden productivity gems inside the editor. It works on any windows.