diff --git a/lisp/wid-edit.el b/lisp/wid-edit.el
index de2b5d4a7c8..35e7b9ce7e1 100644
--- a/lisp/wid-edit.el
+++ b/lisp/wid-edit.el
@@ -131,16 +131,21 @@ This exists as a variable so it can be set locally in certain buffers.")
 			(((class grayscale color)
 			  (background light))
 			 :background "gray85"
+                         ;; We use negative thickness of the horizontal box border line to
+                         ;; avoid making lines taller when fields become visible.
+                         :box (:line-width (1 . -1) :color "gray80")
 			 :extend t)
 			(((class grayscale color)
 			  (background dark))
 			 :background "dim gray"
+                         :box (:line-width (1 . -1) :color "gray46")
 			 :extend t)
 			(t
 			 :slant italic
 			 :extend t))
   "Face used for editable fields."
-  :group 'widget-faces)
+  :group 'widget-faces
+  :version "28.1")
 
 (defface widget-single-line-field '((((type tty))
 				     :background "green3"