In this video, I'll explain how Emacs' display-buffer function is used to determine which window (or frame!) gets used to display a buffer. This is useful when you want to prevent Emacs from breaking your perfectly-organized window layouts! I'll go through many of the built-in "display action" functions to explain how they work. We'll conclude the video by changing our configuration to prevent popup windows from being created and to cause Org Mode and Help buffers to reuse windows containing other buffers for those modes! Keep an eye out for the next video where we will cover display-buffer-alist and custom display action functions! Show notes: https://github.com/daviwil/emacs-from-scratch/blob/master/show-notes/Emacs-Tips-DisplayBuffer-1.org Chapters 0:00 - Intro 0:34 - Popup windows are annoying. 1:48 - How display-buffer works 7:50 - What is an action function? 9:47 - A tour of action function parameters 16:63 - Examining the default placement actions 35:47 - Overriding the default placement actions 41:55 - What's next? My Emacs configuration: https://github.com/daviwil/dotfiles/blob/master/Emacs.org If you enjoy this series, please consider becoming a sponsor on GitHub or Patreon: - https://github.com/sponsors/daviwil - https://patreon.com/SystemCrafters You can also leave a tip via PayPal: https://paypal.me/daviwil Follow me on Twitter for more Emacs content! https://twitter.com/SystemCrafters Chat with the System Crafters community on Discord: https://discord.gg/yVD8Gx6 Intro music: Coriolis Effect by logos feat. stefsax, licensed CC-BY http://ccmixter.org/files/mseq/26296