Sharepoint - Run development and production versions of the SP Fx web parts in two different site collections?

OK, I asjed this in the PNP-JS-COre meeting. Vesa said you can just change the settings in the config files to create a new package. So in config/package solution you can change the solution id and solution name to make it a distict package. Also change the paths Zipped-Package to give it a different file name so that you can have two versions in the app catalog.

Then you can set up an alternate cdnBasePath in write-manifest.json to point to the dev bundle.

Microsoft has now released a site collection app catalog -

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The only limitation appears to be a lack of Application Lifecycle Management API support.