Regression: Mentions in thread title (#18369)

app/threads/client/components/ThreadComponent.js

@@ -88,7 +88,7 @@ export default function ThreadComponent({ mid, rid, jump, room, ...props }) {
 			<VerticalBar rcx-thread-view width='full' style={style} display='flex' flexDirection='column' position='absolute' { ...!expanded && { width: '380px' } }>
 				<VerticalBar.Header>
 					<VerticalBar.Icon name='thread' />
-					<VerticalBar.Text>{headerTitle}</VerticalBar.Text>
+					<VerticalBar.Text dangerouslySetInnerHTML={{ __html: headerTitle }} />
 					<VerticalBar.Action aria-label={expandLabel} onClick={handleExpandButton} name={expandIcon}/>
 					<VerticalBar.Action aria-label={actionLabel} onClick={handleFollowButton} name={button}/>
 					<VerticalBar.Close aria-label={t('Close')} onClick={handleClose}/>

app/threads/client/lib/normalizeThreadTitle.js

@@ -8,7 +8,7 @@ import { MentionsParser } from '../../../mentions/lib/MentionsParser';
 
 export const normalizeThreadTitle = ({ ...message }) => {
 	if (message.msg) {
-		const filteredMessage = filterMarkdown(message.msg);
+		const filteredMessage = filterMarkdown(s.escapeHTML(message.msg));
 		if (!message.channels && !message.mentions) {
 			return filteredMessage;
 		}