how to copy uxp plug-ins form old to new computer

I have just switched to a new computer and, as usual, copied all the default settings etc. to the new computer. Unfortunately, this didn't work with the uxp plugins. Although all plugins are present in ...plugins/external and their settings are present in .../pluginstorage/..., they are not loaded in Photoshop.
Is there any other preferences document where the plugins are registered so that Photoshop can load them?