diff --git a/lisp/international/mule.el b/lisp/international/mule.el
index 9d9c2d46a93..78c02ee870f 100644
--- a/lisp/international/mule.el
+++ b/lisp/international/mule.el
@@ -1760,7 +1760,7 @@ in-place."
 (defcustom auto-coding-alist
   ;; .exe and .EXE are added to support archive-mode looking at DOS
   ;; self-extracting exe archives.
-	  '(("\\.\\(\
+  '(("\\.\\(\
 arc\\|zip\\|lzh\\|lha\\|zoo\\|[jew]ar\\|xpi\\|rar\\|7z\\|squashfs\\|\
 ARC\\|ZIP\\|LZH\\|LHA\\|ZOO\\|[JEW]AR\\|XPI\\|RAR\\|7Z\\|SQUASHFS\\)\\'"
      . no-conversion-multibyte)
@@ -1769,6 +1769,10 @@ ARC\\|ZIP\\|LZH\\|LHA\\|ZOO\\|[JEW]AR\\|XPI\\|RAR\\|7Z\\|SQUASHFS\\)\\'"
     ("\\.\\(gz\\|Z\\|bz\\|bz2\\|xz\\|gpg\\)\\'" . no-conversion)
     ("\\.\\(jpe?g\\|png\\|gif\\|tiff?\\|p[bpgn]m\\)\\'" . no-conversion)
     ("\\.pdf\\'" . no-conversion)
+    ;; https://spec.editorconfig.org/ says:
+    ;;     EditorConfig files must be UTF-8 encoded,
+    ;;     with LF or CRLF line separators.
+    ("/\\.editorconfig\\'" . utf-8-undecided)
     ("/#[^/]+#\\'" . utf-8-emacs-unix))
   "Alist of filename patterns vs corresponding coding systems.
 Each element looks like (REGEXP . CODING-SYSTEM).