From 5aa4d0f8f36aa6d2b5c54c5f3efede6e01cad421 Mon Sep 17 00:00:00 2001
From: Takushi Usami <takushi1969@gmail.com>
Date: Sun, 16 Mar 2025 00:16:05 +0900
Subject: [PATCH] enable to preview with relative images.

---
 markdown-mode.el | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/markdown-mode.el b/markdown-mode.el
index 311050f4..2157ae34 100644
--- a/markdown-mode.el
+++ b/markdown-mode.el
@@ -7663,6 +7663,16 @@ or remove markup."
 
 ;;; Commands ==================================================================
 
+(defun markdown--replace-rel2abs (output-buffer-name)
+  "Convert relative image URLs to absolute paths in OUTPUT-BUFFER-NAME."
+  (let ((buf (get-buffer-create output-buffer-name))
+        (base-path default-directory))
+    (with-current-buffer buf
+      (goto-char (point-min))
+      (while (re-search-forward "<img src=\"\\(\\.[^\"]+\\)" nil t)
+        (let ((arbitrary-name (match-string 1)))
+          (replace-match (concat "<img src=\"" (expand-file-name arbitrary-name base-path) nil nil)))))))
+
 (defun markdown (&optional output-buffer-name)
   "Run `markdown-command' on buffer, sending output to OUTPUT-BUFFER-NAME.
 The output buffer name defaults to `markdown-output-buffer-name'.
@@ -7724,6 +7734,7 @@ Return the name of the output buffer used."
         (unless (eq exit-code 0)
           (user-error "%s failed with exit code %s"
                       markdown-command exit-code))))
+    (markdown--replace-rel2abs output-buffer-name)
     output-buffer-name))
 
 (defun markdown-standalone (&optional output-buffer-name)