Waze pushed the new MTE tool to WME and those with proper permission will be able to set events directly on WME and thereafter associate the closures of the event with the event created.

For guidance on how to use this tool please look at this guide.

Remember that this tool is for Major Traffic Events. Major means that they have meaningful impact on the road users. With that there is no need to send MTE requests to Waze anymore and they can be created directly in WME. If you don't have permission you can request to set an MTE from a fellow editor with permissions.
Regular, everyday closures, should be handled as before and not using this tool.