An SPFx web part that embeds small, self-contained HTML applications (HTML + inline JavaScript + CSS, stored in a SharePoint document library) into SharePoint pages without the SharePoint file-preview chrome (toolbar, download button).
Open this sample in the gallery (popup panel): Open in gallery
Source: https://github.com/pnp/sp-dev-fx-webparts/tree/main/samples/react-copilot-html-app-integrator