handle relative images

src/controllers/topics.js

@@ -288,7 +288,7 @@ function addTags(topicData, req, res) {
 		},
 	];
 
-	var regex = /src\s*=\s*"(.+?)"/g;
+	var regex = /src\s*=\s*"(.+?)"/;
 
 	topicData.posts.forEach(function (postData) {
 		var match = regex.exec(postData.content);
@@ -297,6 +297,9 @@ function addTags(topicData, req, res) {
 			if (image.startsWith(nconf.get('url') + '/plugins')) {
 				return;
 			}
+			if (!image.startsWith('http')) {
+				image = nconf.get('url') + image;
+			}
 			res.locals.metaTags.push({
 				property: 'og:image',
 				content: image,