diff --git a/src/core/components/iframe/iframe.ts b/src/core/components/iframe/iframe.ts
index fdd472b85f8..5836438b984 100644
--- a/src/core/components/iframe/iframe.ts
+++ b/src/core/components/iframe/iframe.ts
@@ -30,6 +30,7 @@ import { CoreSites } from '@services/sites';
 import { toBoolean } from '@/core/transforms/boolean';
 import { CoreDom } from '@singletons/dom';
 import { CoreAlerts } from '@services/overlays/alerts';
+import { CoreLang, CoreLangFormat } from '@services/lang';
 
 @Component({
     selector: 'core-iframe',
@@ -234,9 +235,16 @@ export class CoreIframeComponent implements OnChanges, OnDestroy {
             this.displayHelp = CoreIframeUtils.shouldDisplayHelpForUrl(url);
 
             const currentSite = CoreSites.getCurrentSite();
-            if (this.allowAutoLogin && currentSite) {
-                // Format the URL to add auto-login if needed.
-                url = await currentSite.getAutoLoginUrl(url, false);
+            if (currentSite?.containsUrl(url)) {
+                // Format the URL to add auto-login if needed and add the lang parameter.
+                const autoLoginUrl = this.allowAutoLogin ?
+                    await currentSite.getAutoLoginUrl(url, false) :
+                    url;
+
+                const lang = await CoreLang.getCurrentLanguage(CoreLangFormat.LMS);
+                url = CoreUrl.addParamsToUrl(autoLoginUrl, { lang }, {
+                    checkAutoLoginUrl: autoLoginUrl !== url,
+                });
             }
 
             if (currentSite?.isVersionGreaterEqualThan('3.7') && CoreUrl.isVimeoVideoUrl(url)) {
diff --git a/src/core/directives/format-text.ts b/src/core/directives/format-text.ts
index 9ad3c2ed52b..63857fe912d 100644
--- a/src/core/directives/format-text.ts
+++ b/src/core/directives/format-text.ts
@@ -60,6 +60,7 @@ import { toBoolean } from '../transforms/boolean';
 import { CoreViewer } from '@features/viewer/services/viewer';
 import { CorePromiseUtils } from '@singletons/promise-utils';
 import { CoreAlerts } from '@services/overlays/alerts';
+import { CoreLang, CoreLangFormat } from '@services/lang';
 
 /**
  * Directive to format text rendered. It renders the HTML and treats all links and media, using CoreLinkDirective
@@ -833,7 +834,13 @@ export class CoreFormatTextDirective implements OnChanges, OnDestroy, AsyncDirec
             // Remove iframe src, otherwise it can cause auto-login issues if there are several iframes with auto-login.
             iframe.src = '';
 
-            const finalUrl = await CoreIframeUtils.getAutoLoginUrlForIframe(iframe, src);
+            let finalUrl = await CoreIframeUtils.getAutoLoginUrlForIframe(iframe, src);
+
+            const lang = await CoreLang.getCurrentLanguage(CoreLangFormat.LMS);
+            finalUrl = CoreUrl.addParamsToUrl(finalUrl, { lang }, {
+                checkAutoLoginUrl: src !== finalUrl,
+            });
+
             await CoreIframeUtils.fixIframeCookies(finalUrl);
 
             iframe.src = finalUrl;