diff -u /tmp/breadcrumbs.el.1 /tmp/breadcrumbs.el
--- /tmp/breadcrumbs.el.1	2023-06-08 09:20:18.490560968 +0200
+++ /tmp/breadcrumbs.el	2023-06-08 09:23:13.217684032 +0200
@@ -35,9 +35,9 @@
 ;; https://github.com/gitrj95/breadcrumbs.el
 ;;
 ;; In order to use breadcrumbs, `breadcrumbs-mode' must be enabled.
-;;
-;;; Interface:
-;;
+
+;;;; Interface:
+
 ;; `breadcrumbs-drop-breadcrumb' adds the current position in the
 ;;  buffer to a ring.  If point is at a known breadcrumb, the existing
 ;;  breadcrumb will be moved to the head of the ring.  Adding
@@ -103,28 +103,26 @@
   "Set up the state required to start using breadcrumbs."
   (unless breadcrumbs-ring
     (setq breadcrumbs-ring (make-ring breadcrumb-ring-max)))
-  (mapcar (lambda (fn)
-            (advice-add fn :around #'breadcrumbs--drop-around))
-          breadcrumbs-drop-around-fn-list))
+  (dolist (fn breadcrumbs-drop-around-fn-list)
+    (advice-add fn :around #'breadcrumbs--drop-around)))
 
 (defun breadcrumbs--teardown ()
   "Tear down the state required for breadcrumbs."
   (setq breadcrumbs-ring nil
         breadcrumbs--neighbor nil)
-  (mapcar (lambda (fn)
-            (advice-remove fn #'breadcrumbs--drop-around))
-          breadcrumbs-drop-around-fn-list))
+  (dolist (fn breadcrumbs-drop-around-fn-list)
+    (advice-remove fn #'breadcrumbs--drop-around)))
 
 (defun breadcrumbs--switch-to-fileless-buffer (breadcrumb)
-  "Switch to BREADCRUMB's `fileless-buffer-name' if it is non-nil and optionally remove dead ones."
+  "Switch to BREADCRUMB's `fileless-buffer-name' if it is non-nil.
+Optionally remove dead ones."
   (if-let* ((buffer-name (breadcrumbs--breadcrumb-fileless-buffer-name breadcrumb))
             (buffer (get-buffer buffer-name)))
       (switch-to-buffer buffer)
     (when (yes-or-no-p (format "%s has been killed.  Remove from all instances from `breadcrumbs-ring'? " buffer-name))
-      (mapcar (lambda (breadcrumb-to-remove)
-                (when (equal buffer-name (breadcrumbs--breadcrumb-fileless-buffer-name breadcrumb-to-remove))
-                  (ring-remove breadcrumbs-ring (ring-member breadcrumbs-ring breadcrumb-to-remove))))
-              (ring-elements breadcrumbs-ring))
+      (dolist (breadcrumb-to-remove (ring-elements breadcrumbs-ring))
+	(when (equal buffer-name (breadcrumbs--breadcrumb-fileless-buffer-name breadcrumb-to-remove))
+          (ring-remove breadcrumbs-ring (ring-member breadcrumbs-ring breadcrumb-to-remove))))
       (breadcrumbs-list--revert)
       nil)))
 
@@ -170,7 +168,7 @@
                   ((eq direction 'previous) (ring-next breadcrumbs-ring jump-target)))))
           (breadcrumbs--neighbor
            (when (eq direction 'previous)
-               (breadcrumbs--jump breadcrumbs--neighbor))))))
+             (breadcrumbs--jump breadcrumbs--neighbor))))))
 
 ;;;###autoload
 (define-minor-mode breadcrumbs-mode
@@ -195,9 +193,9 @@
 (defun breadcrumbs--format-breadcrumb (breadcrumb)
   "Return BREADCRUMB's formatted slots as a vector."
   (let* ((buffer-file-name (breadcrumbs--breadcrumb-buffer-file-name breadcrumb))
-	(buffer-position (breadcrumbs--breadcrumb-buffer-position breadcrumb))
-        (buffer-name (breadcrumbs--breadcrumb-fileless-buffer-name breadcrumb))
-        (breadcrumb-name (or buffer-file-name buffer-name)))
+	 (buffer-position (breadcrumbs--breadcrumb-buffer-position breadcrumb))
+         (buffer-name (breadcrumbs--breadcrumb-fileless-buffer-name breadcrumb))
+         (breadcrumb-name (or buffer-file-name buffer-name)))
     (vector
      (breadcrumbs--format-slot breadcrumb-name 64)
      (breadcrumbs--format-slot buffer-position 16))))
@@ -207,7 +205,8 @@
   (mapcar (lambda (breadcrumb)
             (list
              breadcrumb
-             (breadcrumbs--format-breadcrumb breadcrumb))) (ring-elements breadcrumbs-ring)))
+             (breadcrumbs--format-breadcrumb breadcrumb)))
+	  (ring-elements breadcrumbs-ring)))
 
 (defun breadcrumbs-list--revert ()
   "Reverts `breadcrumbs-list-buffer'."
@@ -232,7 +231,7 @@
   (ring-remove breadcrumbs-ring
                (ring-member breadcrumbs-ring (tabulated-list-get-id)))
   (when (ring-empty-p breadcrumbs-ring)
-      (setq breadcrumbs--neighbor nil))
+    (setq breadcrumbs--neighbor nil))
   (breadcrumbs-list--revert))
 
 ;;;###autoload

Diff finished.  Thu Jun  8 09:24:02 2023