SpFx Hide page until WebParts Load
Simply hide the page canvas until all SpFx WebPart promises have resolved for modern sites
This would conceivably
1. Improve page load performance by not forcing the browser to display several loading gifs/fading animations at the same time
2. Improve user experience by displaying a complete page to the user rather than the page "jumping" constantly during the first 3-10 seconds of loading
3. Allow developers to add minor CSS updates to the page prior to render using the SharePoint Framework without noticeable "jumping"
There has to be a better solution than how slow it is currently. Could we provide skeleton UIs or something similar to avoid the perceived impact on loading? https://www.sitepoint.com/how-to-speed-up-your-ux-with-skeleton-screens/
Ideally this would also apply to SpFx Extensions