Steps to reproduce:

1. Try to follow the guide: Microsoft Teams monitoring and integration with Zabbix
2. Based on [Use Microsoft 365 and custom connectors - Microsoft Teams | Microsoft Docs|https://docs.microsoft.com/en-us/microsoftteams/office-365-custom-connectors#add-a-connector-to-a-channel] we get a new webhook URL: https://companyname.webhook.office.com/webhookb2/5bf015e2-ce92-42a8-8e90-92552d6ef161@0c6aa5a3-6531-4e28-9c0b-33ba1a8aa1ff/IncomingWebhook/f7fb2308e5f14431ace5b7cd0e670e42/4563618c-b03b-4e80-b093-28bb4ff11de8
3. On Zabbix Server add new Media Type Webhook with Paraemter teams_endpoint set to the URL
4. If you try to test the new media type you get the following message in webinterface: Sending failed: Invalid MS Teams webhook URL: https://<MSTENTANT>.webhook.office.com/webhookb2/586d2828-cb58-48f6-954d-d5de26c29795@0c6aa5a3-6531-4e28-9c0b-33ba1a8aa1ff/IncomingWebhook/bb06d61118274b82bfe4d9<TenRandomDigits>/4563618c-b03b-4e80-b093-28bb4ff11de8

Result:

Unable to send messages to Teams:
Sending failed: Invalid MS Teams webhook URL: https://<MSTENTANT>.webhook.office.com/webhookb2/586d2828-cb58-48f6-954d-d5de26c29795@0c6aa5a3-6531-4e28-9c0b-33ba1a8aa1ff/IncomingWebhook/bb06d61118274b82bfe4d9<TenRandomDigits>/4563618c-b03b-4e80-b093-28bb4ff11de8

Expected:
Send Messages to Teams

Zabbix Forum Link with fix:
Teams Integration - Invalid MS Teams webhook - ZABBIX Forums

Fix:
In source code 

• zabbix-5.2.x/database/mysql/data.sql modify the 4 entries regarding !params.teams_endpoint.startsWith to !params.teams_endpoint.includes('office.com/webhook'