Hi @Strange, Bethan
According to our tests, when creating a webinar, you need to save the Details page once before proceeding to the next step.
In the Manage Event after creation, if you do not make changes to the meeting, the save pop-up window will not pop up.
You can try using NewTeams and update Teams to the latest version.
At the same time, you don’t need to worry about the save button triggering an email. Attendees will only receive an update email if the meeting date is modified. They will not receive notifications about any other changes.
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