diff --git a/apps/meteor/client/startup/incomingMessages.ts b/apps/meteor/client/startup/incomingMessages.ts
index 4efd3dba0fbf7..eafdb5e1838d3 100644
--- a/apps/meteor/client/startup/incomingMessages.ts
+++ b/apps/meteor/client/startup/incomingMessages.ts
@@ -3,6 +3,7 @@ import type { IMessage } from '@rocket.chat/core-typings';
 import { sdk } from '../../app/utils/client/lib/SDKClient';
 import { onLoggedIn } from '../lib/loggedIn';
 import { getUserId } from '../lib/user';
+import { upsertThreadMessageInCache } from '../lib/utils/threadMessageUtils';
 import { Messages } from '../stores';
 
 onLoggedIn(() => {
@@ -12,6 +13,10 @@ onLoggedIn(() => {
 		msg.u = msg.u || { username: 'rocket.cat' };
 		msg.private = true;
 
+		if (msg.tmid) {
+			upsertThreadMessageInCache(msg, msg.rid, msg.tmid);
+		}
+
 		return Messages.state.store(msg);
 	}).stop;
 });
diff --git a/apps/meteor/tests/e2e/message-mentions.spec.ts b/apps/meteor/tests/e2e/message-mentions.spec.ts
index d03c62edd4f5b..17ea83daa44a8 100644
--- a/apps/meteor/tests/e2e/message-mentions.spec.ts
+++ b/apps/meteor/tests/e2e/message-mentions.spec.ts
@@ -137,17 +137,17 @@ test.describe.serial('message-mentions', () => {
 			});
 
 			await test.step('show "Do nothing" action', async () => {
-				await expect(adminPage.content.lastUserMessage.locator('button >> text="Do nothing"')).toBeVisible();
+				await expect(adminPage.content.getLastMessageActionButton('Do nothing')).toBeVisible();
 			});
 			await test.step('show "Add them" action', async () => {
-				await expect(adminPage.content.lastUserMessage.locator('button >> text="Add them"')).toBeVisible();
+				await expect(adminPage.content.getLastMessageActionButton('Add them')).toBeVisible();
 			});
 			await test.step('show "Let them know" action', async () => {
-				await expect(adminPage.content.lastUserMessage.locator('button >> text="Let them know"')).toBeVisible();
+				await expect(adminPage.content.getLastMessageActionButton('Let them know')).toBeVisible();
 			});
 
 			await test.step('dismiss', async () => {
-				await adminPage.content.lastUserMessage.locator('button >> text="Do nothing"').click();
+				await adminPage.content.getLastMessageActionButton('Do nothing').click();
 			});
 
 			await test.step('receive second bot message', async () => {
@@ -155,7 +155,7 @@ test.describe.serial('message-mentions', () => {
 				await expect(adminPage.content.lastUserMessage.locator('.rcx-message-block')).toContainText(mentionText);
 			});
 			await test.step('send message to users', async () => {
-				await adminPage.content.lastUserMessage.locator('button >> text="Let them know"').click();
+				await adminPage.content.getLastMessageActionButton('Let them know').click();
 				await expect(adminPage.content.lastUserMessageBody).toContainText(getMentionText(Users.user1.data.username, 3));
 			});
 
@@ -164,11 +164,34 @@ test.describe.serial('message-mentions', () => {
 				await expect(adminPage.content.lastUserMessage.locator('.rcx-message-block')).toContainText(mentionText);
 			});
 			await test.step('add users to room', async () => {
-				await adminPage.content.lastUserMessage.locator('button >> text="Add them"').click();
+				await adminPage.content.getLastMessageActionButton('Add them').click();
 				await expect(adminPage.content.lastSystemMessageBody).toContainText('added');
 			});
 		});
 
+		test('should show non-member mention warning inside threads', async ({ page }) => {
+			const adminPage = new HomeChannel(page);
+			const mentionText = getMentionText(Users.user2.data.username, 1);
+
+			await test.step('open thread', async () => {
+				await adminPage.navbar.openChat(targetChannel);
+				await adminPage.content.sendMessage('thread parent for non-member mention warning');
+				await adminPage.content.openReplyInThread();
+				await adminPage.content.waitForThread();
+			});
+
+			await test.step('receive bot message inside thread', async () => {
+				await adminPage.content.sendMessageInThread(getMentionText(Users.user2.data.username));
+				await expect(adminPage.content.lastUserThreadMessage).toContainText(mentionText);
+			});
+
+			await test.step('show actions inside thread', async () => {
+				await expect(adminPage.content.getLastThreadMessageActionButton('Do nothing')).toBeVisible();
+				await expect(adminPage.content.getLastThreadMessageActionButton('Add them')).toBeVisible();
+				await expect(adminPage.content.getLastThreadMessageActionButton('Let them know')).toBeVisible();
+			});
+		});
+
 		test.describe(() => {
 			test.use({ storageState: Users.user1.state });
 
@@ -183,17 +206,17 @@ test.describe.serial('message-mentions', () => {
 				});
 
 				await test.step('show "Do nothing" action', async () => {
-					await expect(userPage.content.lastUserMessage.locator('button >> text="Do nothing"')).toBeVisible();
+					await expect(userPage.content.getLastMessageActionButton('Do nothing')).toBeVisible();
 				});
 				await test.step('show "Let them know" action', async () => {
-					await expect(userPage.content.lastUserMessage.locator('button >> text="Let them know"')).toBeVisible();
+					await expect(userPage.content.getLastMessageActionButton('Let them know')).toBeVisible();
 				});
 				await test.step('not show "Add them action', async () => {
-					await expect(userPage.content.lastUserMessage.locator('button >> text="Add them"')).not.toBeVisible();
+					await expect(userPage.content.getLastMessageActionButton('Add them')).not.toBeVisible();
 				});
 
 				await test.step('dismiss', async () => {
-					await userPage.content.lastUserMessage.locator('button >> text="Do nothing"').click();
+					await userPage.content.getLastMessageActionButton('Do nothing').click();
 				});
 
 				await test.step('receive second bot message', async () => {
@@ -202,7 +225,7 @@ test.describe.serial('message-mentions', () => {
 					await expect(userPage.content.lastUserMessage.locator('.rcx-message-block')).toContainText(mentionText);
 				});
 				await test.step('send message to users', async () => {
-					await userPage.content.lastUserMessage.locator('button >> text="Let them know"').click();
+					await userPage.content.getLastMessageActionButton('Let them know').click();
 					await expect(userPage.content.lastUserMessageBody).toContainText(getMentionText(Users.user2.data.username, 3));
 				});
 			});
@@ -237,17 +260,17 @@ test.describe.serial('message-mentions', () => {
 					await expect(userPage.content.lastUserMessage.locator('.rcx-message-block')).toContainText(mentionText);
 				});
 				await test.step('show "Do nothing" action', async () => {
-					await expect(userPage.content.lastUserMessage.locator('button >> text="Do nothing"')).toBeVisible();
+					await expect(userPage.content.getLastMessageActionButton('Do nothing')).toBeVisible();
 				});
 				await test.step('show "Add them" action', async () => {
-					await expect(userPage.content.lastUserMessage.locator('button >> text="Add them"')).toBeVisible();
+					await expect(userPage.content.getLastMessageActionButton('Add them')).toBeVisible();
 				});
 				await test.step('not show "Let them know" action', async () => {
-					await expect(userPage.content.lastUserMessage.locator('button >> text="Let them know"')).not.toBeVisible();
+					await expect(userPage.content.getLastMessageActionButton('Let them know')).not.toBeVisible();
 				});
 
 				await test.step('dismiss', async () => {
-					await userPage.content.lastUserMessage.locator('button >> text="Do nothing"').click();
+					await userPage.content.getLastMessageActionButton('Do nothing').click();
 				});
 
 				await test.step('receive second bot message', async () => {
@@ -256,7 +279,7 @@ test.describe.serial('message-mentions', () => {
 					await expect(userPage.content.lastUserMessage.locator('.rcx-message-block')).toContainText(mentionText);
 				});
 				await test.step('add users to room', async () => {
-					await userPage.content.lastUserMessage.locator('button >> text="Add them"').click();
+					await userPage.content.getLastMessageActionButton('Add them').click();
 					await expect(userPage.content.lastSystemMessageBody).toContainText('added');
 				});
 			});
@@ -285,13 +308,13 @@ test.describe.serial('message-mentions', () => {
 				});
 
 				await test.step('not show "Do nothing" action', async () => {
-					await expect(userPage.content.lastUserMessage.locator('button >> text="Do nothing"')).not.toBeVisible();
+					await expect(userPage.content.getLastMessageActionButton('Do nothing')).not.toBeVisible();
 				});
 				await test.step('not show "Add them" action', async () => {
-					await expect(userPage.content.lastUserMessage.locator('button >> text="Add them"')).not.toBeVisible();
+					await expect(userPage.content.getLastMessageActionButton('Add them')).not.toBeVisible();
 				});
 				await test.step('not show "Let them know" action', async () => {
-					await expect(userPage.content.lastUserMessage.locator('button >> text="Let them know"')).not.toBeVisible();
+					await expect(userPage.content.getLastMessageActionButton('Let them know')).not.toBeVisible();
 				});
 			});
 		});
diff --git a/apps/meteor/tests/e2e/page-objects/fragments/home-content.ts b/apps/meteor/tests/e2e/page-objects/fragments/home-content.ts
index 4feef449186aa..a17e56af0e652 100644
--- a/apps/meteor/tests/e2e/page-objects/fragments/home-content.ts
+++ b/apps/meteor/tests/e2e/page-objects/fragments/home-content.ts
@@ -544,6 +544,14 @@ export class HomeContent {
 		return this.page.locator('[role="listitem"][aria-roledescription="message"]', { hasText: text });
 	}
 
+	getLastMessageActionButton(name: string): Locator {
+		return this.lastUserMessage.getByRole('button', { name, exact: true });
+	}
+
+	getLastThreadMessageActionButton(name: string): Locator {
+		return this.lastUserThreadMessage.getByRole('button', { name, exact: true });
+	}
+
 	getMessageById(id: string): Locator {
 		return this.page.locator(`[role="listitem"][aria-roledescription="message"][id="${id}"]`);
 	}