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This migration only affects customers who are using the private customization API via NutrientViewer.Configuration#ui. To continue using this, move your existing configuration inside the _blocks property of the ui configuration object. You’ll also see a warning in your console if you’re using the older API.

Earlier:

NutrientViewer.load({
ui: {
// Your config earlier.
},
});

Now:

NutrientViewer.load({
ui: {
// your config earlier
_blocks: {
// Your config goes inside `_blocks` now.
},
},
});