Progressive enhancement
Progressive enhancement starts with functional HTML and layers richer behavior on top.
How it works
Links remain links, forms remain forms, and content remains text. Scripts can improve speed or interaction without becoming the sole route to the information.
How to validate it
Test the same task with scripts blocked, slow, and fully enabled; the destination and essential facts should remain available in every mode.
Common failure
A styled button with only an onclick handler is not an enhanced link; it is a separate JavaScript-only interface.
Machine-readable editions
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