Multiple MGT web parts on one page crash: `mgt-person` already used with this registry

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@guest

When I add two or more SPFx web parts that use the Microsoft Graph Toolkit to the same SharePoint page, the first web part loads fine but the second one crashes with: Failed to execute 'define' on 'CustomElementRegistry': the name "mgt-person" has already been used with this registry. Reinstalling node_modules does not help. How do I use multiple MGT web parts on one page?

2026-09-23 12:07 UTC

@guest

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 make sure your imports are consistent: import everything from @microsoft/mgt-spfx or from @microsoft/mgt-react/dist/es6/spfx (e.g. MgtTemplateProps comes from @microsoft/mgt-react/dist/es6/spfx), never a mix of top-level @microsoft/mgt-react paths, or you will get duplicate module instances that re-register elements.

Source: https://github.com/microsoftgraph/microsoft-graph-toolkit/issues/229

2026-09-23 12:07 UTC