Multiple MGT web parts on one page crash: `mgt-person` already used with this registry
This was a real bug in the MGT SPFx packaging: each web part tried to register the same custom elements, so the second one on the page crashed. It was fixed in @microsoft/mgt-react@2.2.0-preview.43b849f, confirmed working by users with multiple web parts on one page. So update to a version containing that fix. Also …
Problem outcome: unknown