tegwick
d32774da51
Assistant: codex Assistant-Model: gpt-6-astra Assistant-Session: 01a0cffe-206f-7323-89d3-b20ca4cf4bf9
52 lines
2.8 KiB
Markdown
52 lines
2.8 KiB
Markdown
---
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title: Progressive Enhancement
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status: draft
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maturity: hypothesis
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families: [quality, execution, affordance]
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scales: [L3, L6]
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admission: research-candidate-only
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---
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# Progressive Enhancement
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Context: essential reading/navigation or submission should work before optional
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scripts arrive. Problem: delayed or failed client execution can block a usable
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server-delivered interface. Resilience competes with interaction richness and the
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cost of maintaining equivalent behavior across paths.
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Proposed solution: give the essential task a usable HTML/link/form contract first;
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add client behavior that preserves its meaning and authoritative validation.
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Define which controls are essential and what enhanced behavior adds. Test absent,
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late and partially failing scripts separately. Server-rendered text alone does not
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establish a functional no-script task.
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For enhanced navigation, preserve route, history, loading/error feedback and focus
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semantics. For writes, avoid duplicate submission when falling back after an
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uncertain response: reconcile the original operation before resubmitting it.
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Keyboard operation, labels, status announcements and recovery focus need explicit
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verification in both paths. Native elements help but are not an accessibility proof.
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Consequences: initial tasks depend on fewer client capabilities, while parity and
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failure recovery add design work. No-script support is not offline support. A
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client-only rich editor may deliberately require scripts; name that requirement
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instead of promising a fallback that cannot perform the task.
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Evidence: [navigation review](../reviews/NavigationRenderingEvidence.md) N03–N05
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locates htmx and SvelteKit mechanisms with specific link/form/action prerequisites.
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These are two documentation families, not two verified deployments of this complete
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contract. Full-pattern recurrence and decision benefit remain unknown. This develops
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an existing seed; hypothesis only, no canonical identity or admitted relations.
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Proposed connections: [URL-addressable State](URLAddressableState.md) supports shared
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view selection; [Mutation Outcome Tracking](MutationOutcomeTracking.md) matters when
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an enhanced write becomes uncertain. Neither is a universal dependency.
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[VC-03](../walkthroughs/VC03-ContentPublication.md) explores a read-only core.
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## Prospective runtime corroboration — 2026-09-27
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Native links and GET filtering remain usable with JavaScript disabled or htmx
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loading failed. An enhanced 503 keeps the old URL/view, and an explicitly provided
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native recovery link navigates successfully. This does not establish automatic fallback,
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late-script safety, accessible focus/announcements or offline availability.
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See [NH01–NH06](../reviews/NavigationHistoryExperiment.md). One authored application
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with a real package, not independent deployed recurrence. Hypothesis retained.
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