diff --git a/lisp/minibuffer.el b/lisp/minibuffer.el
index 41b20174be1..0cccc46448b 100644
--- a/lisp/minibuffer.el
+++ b/lisp/minibuffer.el
@@ -2586,16 +2586,13 @@ minibuffer-completion-help
              (minibuffer-completion-base (substring string 0 base-size))
              (base-prefix (buffer-substring (minibuffer--completion-prompt-end)
                                             (+ start base-size)))
-             (base-suffix
-              (if (or (eq (alist-get 'category (cdr md)) 'file)
-                      completion-in-region-mode-predicate)
-                  (buffer-substring
-                   (save-excursion
-                     (if completion-in-region-mode-predicate
-                         (point)
-                       (or (search-forward "/" nil t) (point-max))))
-                   (point-max))
-                ""))
+             (base-suffix (let ((suffix (buffer-substring (point) end)))
+                            (substring
+                             suffix
+                             (cdr (completion-boundaries (buffer-substring start (point))
+                                                         minibuffer-completion-table
+                                                         minibuffer-completion-predicate
+                                                         suffix)))))
              (all-md (completion--metadata (buffer-substring-no-properties
                                             start (point))
                                            base-size md
@@ -2697,7 +2694,11 @@ minibuffer-completion-help
                                        (delete-minibuffer-contents)
                                        (insert start choice)
                                        ;; Keep point after completion before suffix
-                                       (save-excursion (insert end)))
+                                       (save-excursion (insert
+                                                        (completion--merge-suffix
+                                                         choice
+                                                         (1- (length choice))
+                                                         end))))
                                    (unless (or (zerop (length prefix))
                                                (equal prefix
                                                       (buffer-substring-no-properties