Backwards-Compatibility across UI Framework major versions
Major version numbers of the UI Framework module are significant, and each major version upgrade (1.x, 2.x, 3.x, etc) introduces backwards-incompatible changes.
3.0
Prior versions of UI Framework automatically wrapped all pages in a standard <html>...</html> template. Since UIFR-104Â this no longer happens, so you need to provide that boilerplate yourself, typically through a common decorator. See how we changed things in the appui module.
2.0
Referring to pages, fragments, and resources, now requires that you indicate the page/fragment/resource provider. See  Upgrading from 1.7 of the UI FrameworkÂ
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