Fix trailing slash issue

main.go

@@ -103,6 +103,9 @@ fsPath := filepath.Join(h.root, filepath.FromSlash(urlPath))
 	}
 
 	if info.IsDir() {
+		if urlPath != "/" {
+			urlPath += "/"
+		}
 		h.serveDir(w, r, urlPath, fsPath)
 	} else {
 		http.ServeFile(w, r, fsPath)
@@ -133,17 +136,12 @@ func (h *handler) serveDir(w http.ResponseWriter, r *http.Request, urlPath, fsPa
 		entries = listEntries(fsPath, urlPath)
 	}
 
-	postURL := urlPath
-	if urlPath == "/" {
-		postURL = "/"
-	}
-
 	data := pageData{
 		Title:      pageTitle(urlPath),
 		Crumbs:     buildCrumbs(urlPath),
 		CanEdit:    true,
 		EditMode:   editMode,
-		PostURL:    postURL,
+		PostURL:    urlPath,
 		RawContent: string(rawMD),
 		Content:    rendered,
 		Entries:    entries,