Set ibuffer-use-other-window in ui/popup/+hacks.el

It was originally set to accommodate the popup system.

core/core-ui.el

@@ -76,7 +76,6 @@ Also see `doom-before-switch-buffer-hook'.")
  max-mini-window-height 0.3
  mode-line-default-help-echo nil ; disable mode-line mouseovers
  mouse-yank-at-point t           ; middle-click paste at point, not at click
- ibuffer-use-other-window t
  resize-mini-windows 'grow-only  ; Minibuffer resizing
  show-help-function nil          ; hide :help-echo text
  split-width-threshold 160       ; favor horizontal splits

modules/ui/popup/+hacks.el

@@ -176,6 +176,10 @@ the command buffer."
   (advice-add #'helm-ag--edit :around #'+helm*pop-to-buffer))
 
 
+;; `ibuffer'
+(setq ibuffer-use-other-window t)
+
+
 ;; `Info'
 (defun +popup*switch-to-info-window (&rest _)
   (when-let* ((win (get-buffer-window "*info*")))