diff --git a/core-server/server/routes/get-tiddler-html.js b/core-server/server/routes/get-tiddler-html.js
index b7a8aa8f6..0f4d89a7c 100644
--- a/core-server/server/routes/get-tiddler-html.js
+++ b/core-server/server/routes/get-tiddler-html.js
@@ -33,8 +33,8 @@ exports.handler = function(request,response,state) {
 		}
 		var text = state.wiki.renderTiddler(renderType,renderTemplate,{parseAsInline: true, variables: {currentTiddler: title}});
 
-		// Naughty not to set a content-type, but it's the easiest way to ensure the browser will see HTML pages as HTML, and accept plain text tiddlers as CSS or JS
-		state.sendResponse(200,{},text,"utf8");
+		var headers = {"Content-Type": renderType};
+		state.sendResponse(200,headers,text,"utf8");
 	} else {
 		response.writeHead(404);
 		response.end();
diff --git a/editions/tw5.com/tiddlers/releasenotes/5.4.0/#9203.tid b/editions/tw5.com/tiddlers/releasenotes/5.4.0/#9203.tid
new file mode 100644
index 000000000..13ef89ad7
--- /dev/null
+++ b/editions/tw5.com/tiddlers/releasenotes/5.4.0/#9203.tid
@@ -0,0 +1,10 @@
+title: $:/changenotes/5.4.0/#9203
+description: Fix not provide content-type header in GET routes
+release: 5.4.0
+tags: $:/tags/ChangeNote
+change-type: bugfix
+change-category: nodejs
+github-links: https://github.com/TiddlyWiki/TiddlyWiki5/pull/9203
+github-contributors: linonetwo
+
+Fixed an issue which prevented plugins like the sitemap plugin from setting the correct MIME types (e.g., application/xml).