diff --git a/web/react/utils/markdown.jsx b/web/react/utils/markdown.jsx
index 78d2b801d3..aff776d056 100644
--- a/web/react/utils/markdown.jsx
+++ b/web/react/utils/markdown.jsx
@@ -41,7 +41,7 @@ export class MattermostMarkdownRenderer extends marked.Renderer {
             output += ' title="' + title + '"';
         }
 
-        if (outHref.lastIndexOf(Utils.getTeamURLFromAddressBar()) === 0) {
+        if (outHref.lastIndexOf(Utils.getTeamURLFromAddressBar(), 0) === 0) {
             output += '>';
         } else {
             output += ' target="_blank">';
diff --git a/web/react/utils/text_formatting.jsx b/web/react/utils/text_formatting.jsx
index 43b212484a..b8ed58258b 100644
--- a/web/react/utils/text_formatting.jsx
+++ b/web/react/utils/text_formatting.jsx
@@ -97,7 +97,7 @@ function autolinkUrls(text, tokens) {
         const alias = `MM_LINK${index}`;
 
         var target = 'target="_blank"';
-        if (url.lastIndexOf(Utils.getTeamURLFromAddressBar()) === 0) {
+        if (url.lastIndexOf(Utils.getTeamURLFromAddressBar(), 0) === 0) {
             target = '';
         }