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Step 3 - Converting legacy UIs

The UI object, which represents the <body> element in the page, is controlled by Flow when running the MPR, so anything extending UI should be converted. Actually, UI class should not be used for layouting or navigation handling anymore. At the end of step 3, you should not have any UI class unless you have a real use case for it.

There are several conversion paths, depending on what’s used in the project: