hyper_render 1.6.0

Render HTML/Markdown/Delta at 60 FPS. The only Flutter renderer with CSS float layout, crash-free text selection, and CJK Ruby typography. Drop-in flutter_html alternative.

Changelog

1.6.0

⚠️ Behavior Change — text now scales with system accessibility settings

• Rendered text now honours the device's accessibility text-scaling setting (WCAG 2.1 AA §1.4.4, "Resize Text"). Previously HyperRender ignored MediaQuery.textScaler entirely — a paragraph rendered at the same pixel size regardless of the user's "large text" OS setting, unlike every Flutter Text widget. It now reads MediaQuery.textScalerOf(context) and applies it to every measured/painted text fragment. This means existing content will re-render larger for users who have increased their system font size — the correct, accessible behavior, and consistent with Flutter's Text/RichText. To opt a specific viewer out (fixed-size rendering), pass HyperRenderWidget(textScaler: TextScaler.noScaling) or wrap it in a MediaQuery with TextScaler.noScaling. Found by cross-referencing flutter_html issue #308.

✨ New CSS Features

• text-align now executes for paragraph text (center / right / justify). Previously text-align only applied to widget-tier content (table cells, flex) — plain <p>/<div> text painted on the canvas ignored it and always left-aligned, despite the docs claiming support. Selection and hit-testing follow the aligned position correctly. justify distributes free space across each line's inter-word gaps (widening spaces via word-spacing) so every line but the last reaches the right edge; the trailing wrap-space is excluded so the final glyph lands exactly at the edge. A box-level RTL tree (textDirection: rtl) now honours an explicit text-align (an unset RTL paragraph still right-packs); justify in RTL keeps the start edge for now.
• text-indent now executes — indents the first line of a block (px/em/rem/pt; inherits). It previously had no effect at all despite being listed as supported.
• max-width now constrains a block's content width — text wraps inside the max-width rather than the full container width.
• min-width now executes — raises a block's content width, and wins over max-width per CSS. Previously parsed but ignored.
• Percentage width / max-width / text-indent now resolve against the containing block's content width at layout time (e.g. width: 50%, max-width: 25%, text-indent: 10%). Nested percentages resolve against the parent, not the viewport. % height is still unsupported (needs a deferred-height model — see LIMITATIONS.md).
• border-collapse: separate + border-spacing now execute on tables. Previously the table renderer conflated the inter-cell gap and the border line thickness into a single value and never read border-collapse/border-spacing from CSS. The gap is now a distinct quantity: separate mode reserves a border-spacing gap (UA-default 2px) between cells and around the table edge, and paints a per-cell outline instead of merged grid bars. The default remains collapse (deviating from the CSS initial value separate) to preserve the existing grid rendering byte-for-byte; border-spacing has no effect without border-collapse: separate. Single spacing value and one shared border width (per-cell differing widths not applied) — see LIMITATIONS.md. Minor visible change: a table that explicitly set border-collapse: separate previously fell back to grid bars (the property wasn't parsed); it now renders separated cells. This affects only content that opted into separate — the default and all collapse tables are unchanged.
• Docs correction: CSS_PROPERTIES_MATRIX.md previously over-claimed several properties as supported (text-align/text-indent didn't execute, min-width wasn't implemented) and under-claimed others (border-spacing marked "Not implemented" after it shipped). The matrix now reflects what actually executes, and a new docs_matrix_sync_test.dart fails CI if an execution-verified property is downgraded or a structurally-unsupported one is marked fully supported.
• animation-play-state: running / paused now parsed (longhand and inside the animation shorthand) and executed. A paused animation holds its current frame; flipping back to running resumes from that frame — mid-flight for finite and infinite (repeat()) animations alike. When paused before the initial animation-delay elapses, the delay countdown restarts on resume. Exposed as ComputedStyle.animationPlayState (HyperAnimationPlayState) and HyperAnimatedWidget.paused.
• Canvas-tier block animation: animation-name now executes on plain paragraphs/divs painted directly by RenderHyperBox's canvas, not just widget-tier content (flex/grid containers, plugins, atomic elements). A <div style="animation: fade 1s ease infinite"> now actually animates regardless of which render tier its content uses. Driven by a SchedulerBinding frame loop (no TickerProvider, matching the existing image-loading shimmer's architecture) that stops scheduling once nothing is running. Respects animation-play-state — a paused block holds its frame on the canvas exactly like the widget tier. opacity composites a block's decoration and text together in one saveLayer (fading the result once) instead of fading each independently, which would otherwise double-blend a block's own background showing through its own text; that layer's clip bounds float with the block's transform rather than being pinned to its pre-transform rect, so opacity and transform combine correctly instead of clipping a translated/scaled block to its original position. Scope: a block's own decoration + its own text/ruby fragments only; see LIMITATIONS.md for what does not yet compose (nested animated blocks, list markers, floats, inline decorations).

🔒 Security

• Root HtmlAdapter gained the URL-safety gate it was missing — the adapter HyperViewer actually uses (lib/src/parser/html/html_adapter.dart) previously resolved <a href>/<img src> without checking the scheme, unlike the hyper_render_html, Markdown, and Delta adapters. A caller using HtmlAdapter directly, or with sanitize:false, could let javascript:/file:/data: reach link-tap and image-loading. Now routed through UrlSafety.isSafe (unsafe hrefs → #, unsafe img src → empty), matching the other adapters as defense-in-depth.

📦 Packaging & Tooling

• Pana 160/160 Pub Points: Fully declared platforms: across all 8 sub-packages, bringing the entire ecosystem to the maximum possible pub.dev score. Also resolved missing constructor documentation comments.
• Code Hygiene: Scanned and completely eradicated temporary debug comments (TODOs, non-English placeholder strings) from the core codebase.

🐛 Bug Fixes

• Animation iteration counter leaked across rebuilds: when HyperAnimatedWidget rebuilt its controller (animation name, duration, curve, or keyframes changed), the internal iteration counter kept its old value, so the new animation could stop after fewer iterations than its animation-iteration-count. The counter now resets on every controller rebuild.
• line-height in absolute units used the wrong reference font-size: h2 { font-size: 20px; line-height: 3px } divided the 3px by the parent's font-size (e.g. the default 16px) instead of the element's own 20px, producing a visibly wrong line-height whenever font-size and a length-based line-height were set on the same element — a very common CSS pattern. Found while auditing flutter_html's issue tracker for bugs (#1367) also worth checking against HyperRender's independent implementation.
• <p>&nbsp;</p> collapsed to zero height: a text run made up solely of   (U+00A0) was misclassified as insignificant/collapsible whitespace and dropped, because String.trim() and RegExp's \s both also match U+00A0 — unlike CSS, which explicitly does not. A paragraph holding only a non-breaking space now renders with the same height as any other text paragraph. New shared isCssWhitespaceOnly/cssWhitespaceRun helpers in hyper_render_core replace the ad-hoc .trim().isEmpty/\s+ checks in both HtmlAdapter implementations and the layout tokenizer. Also found via flutter_html's issue tracker (#1439).
• Flutter Web crash parsing CSS transform keyframes: @keyframes with a translate()/scale() step used a negative-lookbehind regex ((?<![XY])translate\(…) that throws Invalid regular expression on Flutter Web and older Safari, crashing the whole widget. The lookbehind was redundant (translate\( already excludes translateX(/translateY() and has been removed — transform animations now parse identically but without the web-incompatible construct. Found via flutter_html #1504/#1314.
• <ol start="N"> ignored: ordered lists always numbered from 1, disregarding the HTML start attribute. <ol start="5"> now numbers 5, 6, 7…; a missing or malformed value still defaults to 1, and sibling lists keep independent counters. Found via flutter_html #1480.
• Malformed CSS with non-finite values crashed layout: an overflowing length literal such as 1e999px parses to Infinity (Dart's double.tryParse accepts it), which propagated into margins/font-sizes/box constraints and threw a BoxConstraints assertion during layout — malformed or hostile CSS (common in email HTML) could crash the app. Length/size/font-size parsing now rejects non-finite results (including overflow after unit scaling), so the declaration is ignored as CSS requires. Found via flutter_widget_from_html #34.
• display: none was parsed but not executed on the canvas path: hidden elements — and hidden <tr>/<td> in tables — still rendered, took up space, and were selectable. Content commonly hidden with display:none (email pre-headers, conditional CMS blocks, tracking wrappers) leaked into the visible/selectable output. Now removed from the box tree at tokenization and from the table grid. Found via flutter_widget_from_html #488.
• First block with padding but no top margin lost its padding: the block-start fragment that carries a block's padding was elided for a first no-margin block (only width constraints re-triggered it). A first <div style="padding:…"> silently rendered flush; <p> was unaffected only because it has a default top margin. Caught by the new CSS-execution guard test. The emission guard now also fires on non-zero padding.
• <a> without href was styled as a link: a placeholder anchor like <a name="x">Text</a> got the blue link colour and underline. Browsers only style a[href]; HyperRender now matches, leaving href-less anchors as plain text. Found via flutter_widget_from_html #676.
• Bootstrap 4/5 logical float classes split away from their content in large documents: the root HtmlAdapter (the one HyperViewer runs) recognised float-left/float-right but not float-start/float-end, so a block floated with the Bootstrap 4/5 utilities could be chunked into a different virtualized section than the text meant to wrap around it. Both adapters now share one superset heuristic (Bootstrap pull-*/float-*/float-start/float-end, Tailwind, WordPress align*, legacy float attribute + inline float: style).

⚠️ Potentially breaking — three transitive dependencies removed

• hyper_render no longer depends on hyper_render_html, hyper_render_markdown or hyper_render_highlight. These were declared but never imported: the root package implements its own HTML/Markdown/highlight parsing directly on html/csslib/markdown/flutter_highlight, so the three packages were pure install weight for every consumer.

  Rendering behaviour is completely unchanged — HyperViewer never used those packages. Nothing breaks if you only import package:hyper_render/hyper_render.dart.

  What can break: code that imports package:hyper_render_html/... (or _markdown / _highlight) while declaring only hyper_render in its pubspec. That used to resolve transitively and will now fail to resolve. Fix by depending on the package explicitly — which is what pub expects for any package you import directly:

  dependencies:
    hyper_render: ^1.6.0
    hyper_render_html: ^1.5.1   # add this if you import it directly
  

  All three remain separately published and fully supported for standalone use.

♻️ Internal

• Deprecation annotations that actually warn: TableParentData carried only a /// @deprecated doc comment, which the analyzer ignores — callers got no warning for a class the renderer never uses. It now has a real @Deprecated(...) annotation, as do the ignored SmartTableWrapper.minScaleFactor / minColumnWidth parameters. All three are slated for removal in v2.0; nothing is removed in this release.

• Removed a stale tracked pubspec.yaml.backup (pinned at v1.4.0 while the real pubspec was v1.5.0) and fixed the publish script's restore instruction, which told you to cp from that file — following it would have silently downgraded the version. It now says git checkout pubspec.yaml.

• Documented the root ↔ sub-package parser duplication in LIMITATIONS.md, including which copy HyperViewer actually runs, so a parser fix isn't applied to only one of them (this has already caused two bugs).

• CI: the weekly benchmark job now alerts on failure — a scheduled-run failure opens (or comments on) a tracking issue instead of sitting as an unwatched red X, so a silent breakage like the month-long mkdir typo surfaces immediately.

• Timing-curve resolution, keyframe-name lookup, and the translate/scale/rotate transform matrix used to build a CSS animation frame are now shared top-level helpers (curveFromHyperTiming, resolveHyperKeyframes, matrix4FromHyperKeyframe in animation_controller.dart) instead of being duplicated between the widget-tier and canvas-tier animation code.

1.5.0 - 2026-07-05

✨ New CSS Features

• cubic-bezier() and steps() timing functions: transition and animation/animation-timing-function now accept cubic-bezier(x1, y1, x2, y2) (mapped to Flutter's Cubic), steps(n, start|end), and the step-start/step-end keywords (via the new HyperStepsCurve). Parameters are carried on HyperTimingParams (HyperCubicBezierParams / HyperStepsParams) so the existing enum-based API stays source-compatible. Shorthand parsing is now paren-aware, so cubic-bezier(0.4, 0, 0.2, 1) is no longer split on its inner commas. x control points are clamped to [0, 1] per spec.
• Animatable color / background-color: @keyframes and transition can now animate text and background colors. HyperKeyframe gained color/backgroundColor fields interpolated with Color.lerp; HyperAnimatedWidget applies them via DefaultTextStyle.merge + ColoredBox, and HyperTransitionWidget animates them via AnimatedDefaultTextStyle + AnimatedContainer. Colors are parsed through the shared StyleResolver.parseCssColor so keyframe colors use the exact same grammar (#hex, rgb(), rgba(), named) as the rest of the engine.

🩺 Diagnostics

• Debug-mode memory-pressure metrics: on didHaveMemoryPressure, HyperViewer now records a HyperMemoryMetrics snapshot (bytes freed from the image cache, images evicted, RenderHyperBox instances cleared, pending image loads dropped) to HyperMemoryDebug in debug builds. Zero cost in release (guarded by kDebugMode; the notifier stays null). Added LazyImageQueue.pendingCount.

🐛 Bug Fixes

• Issue #12 — zero-width BorderSide + border-radius assertion: a CSS element with border-radius and an uneven border (e.g. border-left: 5px solid with the other sides 0px) produced BorderSide(width: 0, style: solid), which Flutter's BoxDecoration rejects as a hairline border when the radius is non-zero. Zero-width sides now map to BorderSide.none via a shared cssBorderFromStyle helper, fixing both the flex-child path (hyper_render_widget.dart) and the flex-container path (flex_container_widget.dart); the latter also now honours border-style: none.
• Color parsing hardened: StyleResolver.parseCssColor now returns null instead of throwing FormatException on malformed hex (#zzz) or out-of-int64 rgb()/rgba() channel values. This matters because color parsing now runs on arbitrary @keyframes values, where a hostile or typo'd color could otherwise crash a render.

1.4.0 - 2026-06-24

✨ New CSS Features

• aspect-ratio: W/H ratio syntax (16/9) and bare-number syntax (2.5) parsed and applied to <img>/<video> sizing — overrides the image's intrinsic ratio when only one dimension (or neither) is specified in CSS/HTML.
• transition execution: CSS transition is now actually animated, not just parsed. New HyperTransitionWidget detects opacity/transform changes across rebuilds and animates them over the declared duration and timing function via AnimatedOpacity/AnimatedContainer. Wired into the render pipeline through _maybeAnimate in hyper_render_widget.dart.
• animation-iteration-count: infinite: now loops via AnimationController.repeat() instead of a one-shot forward(). Added a dedicated alternate flag to HyperAnimatedWidget so animation-direction: alternate / alternate-reverse no longer gets conflated with plain reverse.
• Cross-Chunk Float Carryover — paint completion: the previously-unused imagePixelOffset on FloatCarryover is now consumed at paint time. A tall floated image that overhangs a virtualized section boundary continues painting from the correct offset in the next chunk instead of the gap being left blank.
• ~25 previously-silent CSS properties now resolved: white-space, word-spacing, text-transform, text-decoration-color, min/max-width/height, overflow/overflow-x/overflow-y, border-top/border-right/border-bottom/border-color/border-width, animation shorthand and all animation-* sub-properties, transition, aspect-ratio. These had ComputedStyle fields but no resolver case, so values were silently dropped.

🐛 Bug Fixes

• rem units silently failed — _parseLength had no rem branch; '2rem'.endsWith('em') matched the em branch instead, producing an unparseable '2r'. Added the missing rem case ahead of em.
• text-decoration incorrectly marked as inherited — not an inheritable CSS property per spec; child elements were wrongly picking up a parent's underline/strikethrough. Removed from inheritFrom(); added correct inheritance of text-transform instead.
• Linear-gradient diagonal corners wrong — for to top right / to bottom right / to top left / to bottom left, only begin was corrected, leaving end on the wrong single axis.
• filter only composed the first two entries — multiple chained filters (e.g. blur() brightness() contrast()) silently dropped everything past the second; now folds over the full list.
• border: none left a 1px border — shorthand parsing didn't zero the width when style was none.
• Division-by-zero in line-height — unitless line-height against a zero/null parent font size could divide by zero.
• Float layout list-spread bug — performLayout iterated [..._leftFloats, ..._rightFloats], allocating a new list every line; replaced with two direct loops.
• HyperTextSelection missing operator== — every selection update looked "changed" even when identical, causing redundant repaints.
• setGlobalTextCacheSize leaked old TextPainters on resize — old cache was dropped without disposal.
• Delta adapter indent operator-precedence bug — ((attributes['indent'] as int?) ?? 0 + 1) added 1 to the default before the null-check applied; also hardened the int cast to num.toInt() against JSON-decoded doubles.
• Delta underline+strikethrough mutually exclusive — applying both attributes silently dropped underline; now combined via TextDecoration.combine.
• HTML adapter shared mutable default styles — _defaultStyles[tagName] returned a shared ComputedStyle instance reused (and mutated) across unrelated nodes; now .copyWith()'d per node.
• Markdown adapter didn't normalize \r\n/\r line endings before splitting, breaking line-based heuristics on Windows-authored content.
• Markdown adapter double-applied syntaxes when both extensionSet and explicit blockSyntaxes/inlineSyntaxes were supplied.
• _prebuiltDocument fast-path left stale cached state (_docKeyframes, _cachedEffectiveConfig, _sectionHashes, page count, section boxes) when switching to a pre-parsed AST document.
• pub.dev pana INFO: suppressed the cacheExtent deprecation hint (scrollCacheExtent isn't available on the SDK floor this package supports) with // ignore: deprecated_member_use, consistent with the existing SDK-version-gap pattern.

📝 Documentation

• doc/LIMITATIONS.md: removed stale "not parsed" entries for background-position/background-repeat/list-style-* (shipped in v1.3.1); added v1.4.0 entries; corrected the async-parsing description (Future.microtask, not compute() isolate).
• doc/ROADMAP.md: marked Cross-Chunk Float Carryover paint offset, CSS transition execution, animation-iteration-count: infinite, and aspect-ratio as completed.

1.3.4 - 2026-06-04

🔧 Fixes & Optimizations

• Static Analysis Compliance: Suppressed deprecated SizeTransition.axisAlignment lints with // ignore: deprecated_member_use to maintain backwards compatibility with older Flutter SDKs (>=3.10) while securing 160/160 points on pub.dev.
• Dependency Widening: Widened share_plus dependency constraint to ^12.0.2 || ^13.0.0 in hyper_render_clipboard and root packages to allow compatibility with latest stable release.

1.3.3 - 2026-06-04

🚀 Production Readiness

• Publishing Candidate: Comprehensive code cleanup, removal of unnecessary TODOs, and linting fixes.
• Test Coverage Verified: Passed 973 test cases covering unit, integration, system, performance, stress, and security testing.
• Dependency Resolution: Ensured all internal sub-packages (hyper_render_math, etc.) are fully resolved and analyzed.

✨ New CSS Properties

• object-fit: cover, contain, fill, none, scale-down — applies to <img> elements. Controls how the image content is resized to fit its layout box. Previously, images incorrectly fell through to the background-size mapping; object-fit now takes priority as the semantically correct property for replaced elements.

✨ New Features

• onMemoryPressure callback: HyperViewer now exposes an optional VoidCallback? onMemoryPressure parameter (available on all constructors: default, .delta, .markdown, .fromNode). Invoked after HyperRender clears its internal TextPainter, image, and painting caches in response to didHaveMemoryPressure. Enables host apps to release their own resources (video players, download queues, custom caches) in the same memory-pressure cycle.

🔧 Improvements

• Float carryover imagePixelOffset: FloatCarryover now carries an imagePixelOffset field computed from the originating section's layout. When a tall float image overhangs a virtualized section boundary, the offset records how many pixels of the image were already painted — enabling future visual rendering of the remaining portion in the next section without repeating the top. The _onFloatCarryover comparison in HyperViewer now includes imagePixelOffset to avoid missing updates.

📝 Documentation

• ROADMAP corrected: list-style-type and list-style-position were marked as incomplete ([ ]) despite being fully shipped in v1.3.1. Now correctly marked as [x]. object-fit moved from Backlog to Completed.

---

1.3.2 - 2026-05-18

Bug Fixes (Critical)

• [DEADLOCK] LazyImageQueue no longer deadlocks on a synchronously-throwing loader — if a user-supplied HyperImageLoader threw before invoking its onLoad/onError callback, _active was never decremented; after maxConcurrent such throws the queue stopped processing every subsequent image until app restart. _startLoad now wraps the loader call in try/catch and routes any synchronous exception through the same idempotent error path used by the async callback.
• [SECURITY] Sanitizer now validates ALL URL-bearing attributes — previously only href and src were checked, leaving poster, data, cite, background, longdesc, usemap, manifest, xlink:href, formaction, action, icon, and srcset as XSS bypass vectors (e.g. <video poster="javascript:...">). Added urlBearingAttributes constant and routes every match through isSafeUrl. srcset is split into candidates and each candidate's URL is validated independently.
• [SECURITY] isTap no longer fires when the pointer never went down inside the widget — handleEvent previously treated downPosition == null as a valid tap, so a finger swiping into the widget from outside and lifting up would trigger onLinkTap on whatever fragment was under the lift point. Now requires BOTH a recorded down position AND a movement within tapSlop.
• [BUG-1] Images no longer permanently disappear after a Low Memory Warning — clearMemoryCaches() disposed the image cache but never re-triggered _loadImages(). Visible images were stuck in the empty-placeholder state until the user scrolled the section out of view and back to force a detach+attach cycle. The cache-clear path now re-enqueues image loads via LazyImageQueue so visible images reload through the normal priority pipeline.
• [BUG-2] _hashSection now invalidates on attribute changes — the previous fingerprint only hashed text content + child count, so changing only <img src="a.jpg"> → <img src="b.jpg"> (or class/id/style) produced the same hash. _mergeSections would silently reuse the stale DocumentNode, freezing dynamic UI at the first rendered version. The new recursive hash walks the subtree and includes tagName, type, text, atomic src/alt, all attributes (keys sorted), and per-depth child counts.
• [BUG-3] Eliminated 1-frame layout flash with dangling floats — _onFloatCarryover previously deferred the cross-section update via addPostFrameCallback + setState, so section N+1 always laid out once with empty initialFloats before the corrected pass. Added onRenderBoxReady callback on HyperRenderWidget and VirtualizedChunk; _HyperViewerState keeps a Map<int, RenderHyperBox> registry and pushes new floats directly onto section N+1's RenderObject during section N's layout, so the pipeline owner picks up the change in the same frame.
• [C-1] HyperSelectionOverlay now forwards config, pluginRegistry, enableComplexFilters — plugins, custom link schemes, keyframe animations and filter settings were silently ignored in sync+selectable and paged+selectable modes. All three params are now accepted by HyperSelectionOverlay and forwarded to the inner HyperRenderWidget.
• [C-2] Fixed GPU memory leak in image cache — _imageCache was missing an onEvict callback, so ui.Image GPU textures were never disposed when entries were evicted from the LRU. Added onEvict: (ci) => ci.image?.dispose() to free GPU memory promptly on eviction.
• [C-3] Removed dead _parseIsolate / _parseReceivePort code — these fields were declared but never assigned, making _cancelParsing() a no-op. Cleaned up unused dart:isolate import and fields; _parseId counter remains the mechanism for discarding stale parse results.
• [C-4] TextPainter global cache now respects HyperRenderConfig.textPainterCacheSize — was hardcoded to 500 regardless of config (default 5000). Added RenderHyperBox.setGlobalTextCacheSize() static method; HyperViewer calls it in initState and didUpdateWidget.

Bug Fixes (High)

• [H-1] HyperRenderConfig.operator== and hashCode now include useMicrotaskParsing — changing only this field no longer fails to trigger a re-parse.
• [H-2] ComputedStyle.copyWith() now copies _explicitlySet — previously the result had an empty explicit-set, causing inheritFrom() to overwrite all copyWith'd properties with parent styles, breaking the CSS cascade.
• [H-3] _containsFloatChild detects float:left (no space) and Bootstrap/Tailwind class names — float:left, float-left, float-right, float-start, float-end, pull-left, pull-right are now detected, preventing incorrect section splits in virtualized mode.
• [H-4] isSafeUrl() blocks file:, mhtml:, and about: schemes — these can access local filesystem, trigger MHTML exploits, or enable sandbox-escape via about:blank on Android/iOS.

Bug Fixes (Medium)

• [M-1] _effectiveConfig is now cached — was allocating a new HyperRenderConfig on every build() call (every scroll frame). Cache is invalidated when renderConfig, allowedCustomSchemes, or document keyframes change.
• [M-2] HyperViewer.fromNode now accepts pluginRegistry and onError — previously hardcoded to null, making plugins and error handling unavailable for pre-parsed AST consumers.
• [M-3] _buildPagedContent no longer allocates a discarded HyperRenderWidget — restructured to if/else so only one widget is built per page in selectable mode.
• [M-4] _TextPainterKey now includes wordSpacing — two fragments with identical text but different word-spacing no longer share the same TextPainter, preventing incorrect layout widths.

Performance (Low)

• [L-1] LazyImageQueue._findQueued is now O(1) — added _urlToQueued secondary index; previously O(N) causing O(N²) batch behavior with many simultaneous image loads.
• [L-2] _hasDetailFragments flag replaces O(N) scan — performLayout no longer scans all fragments to check for <details> elements; flag is set during tokenization.

Fixes (Low)

• [L-3] _splitIntoSections no longer overwrites existing node parents — changed child.parent = current to if (child.parent == null) child.parent = current to avoid corrupting ancestor-chain traversal on reused section nodes.
• [L-4] Removed dead _draggingHandle field from HyperSelectionOverlayState.

Correctness & Robustness

• Hash collision resilience on Web — _accumulateHashParts now also mixes in text.length for every TextNode, significantly reducing the chance that two long-but-distinct strings hash to the same slot on the JS target (where Object.hashAll has weaker dispersion than the Dart VM).
• computeMinIntrinsicWidth handles icon fonts, emoji, and dingbats — the previous "longest-by-char-count word" heuristic miscalculated when a single PUA glyph (Material Icons, Font Awesome) or emoji renders far wider than a Latin letter. When the fragment contains any code point in U+E000–U+F8FF, U+2600–U+27BF, or U+1F000+, the entire fragment is measured instead of just the longest word.
• RenderHyperBox.detach() now cancels shimmer state — a ListView item that detached mid-shimmer (scrolled out of cache) and later re-attached kept a stale _shimmerEpoch, producing a 1-frame phase jump on re-mount. The frame callback is now cancelled and _shimmerEpoch reset.

New

• HyperRenderConfig.useRepaintBoundary (default true) — opt out of the outer-section RepaintBoundary wrapper. RenderHyperBox is already an internal repaint boundary, so this is mostly an escape hatch for very low-RAM Android devices (≤ 1.5 GB) rendering image-heavy long documents with a custom small virtualizationChunkSize, where many concurrent GPU layers could exhaust VRAM before the texture cache evicts.

Second-Pass Senior Review (2026-05-18 → 2026-05-19)

A second multi-disciplinary review (PM/BA/SA/principal mobile) surfaced a further batch of issues addressed in this same release. Highlights:

Security

• UrlSafety consolidated in hyper_render_core/util/url_safety.dart — root HtmlSanitizer.isSafeUrl and the hyper_render_markdown sub-package's URL gate previously had independent copies that drifted: the sub-package missed file:/mhtml:/about:. Both now delegate to the shared helper; no future drift is possible.
• HtmlAdapter defence-in-depth URL gate — <img src> and <a href> are now routed through UrlSafety.isSafe even when the upstream HtmlSanitizer is bypassed (callers that invoke HtmlAdapter().parse() directly or render with sanitize: false). Blocked href collapses to #; blocked src collapses to ''.
• hyper_render_clipboard filename hardening (path traversal) — _getFilenameFromUrl already stripped path separators from URL-decoded filenames, but saveImageBytes(filename:) and shareImageBytes(filename:) concatenated caller-supplied strings raw. Every save/share path now runs through a single _sanitiseFilename helper.
• Markdown inline HTML pre-sanitised — when HyperViewer.markdown(sanitize: true) (default) is used with enableInlineHtml: true (default), raw <script>/<style>/<iframe> blocks are now stripped via HtmlSanitizer before reaching the markdown parser, so they can no longer flash as visible text or become a self-rendering plugin's XSS surface.

Layout & Selection

• Unbounded-width crash fixed — RenderHyperBox.performLayout and _computeHeightForWidth clamp _maxWidth to a finite fallback when the constraint is double.infinity (Row without Expanded, horizontal SingleChildScrollView). Before this, _FlexFragment.layout propagated infinity into a BoxConstraints(minWidth: ∞) and tripped Flutter's minWidth < double.infinity assertion.
• text-overflow: ellipsis no longer leaks hidden text via copy — Fragment.ellipsisVisibleLength tracks how many leading characters survive each truncation pass; getSelectedText clamps the visible range against it and skips fully-suppressed fragments. State is reset at the top of every _performLineLayout so a wider re-layout un-hides previously truncated text.
• Selection-drag hit-test made lenient — _lineIndexAt accepts a clampOutOfBounds flag (true for drag, false for tap). When a selection handle drags past the first/last line by a pixel, the index now snaps to the nearest line instead of returning -1 and freezing.
• Dead-code removal — _characterToFragment / _fragmentRanges fields in RenderHyperBox were populated each layout but never read; deleted along with their clear() and populate loops.
• Table cell block-content fallback — when cellContentBuilder is null and a cell contains <div>/<p> children, _buildCellContent now renders the inline run plus each block child via a default Column/Text fallback instead of dropping the content. (Previously only HyperRenderWidget callers were safe.)
• Table grid total-cell cap — added _kMaxTotalCells = 100 000. A pathological <table> whose rowCount × columnCount exceeds the cap now renders a visible "Table too large to render" placeholder instead of allocating an 8 MB null grid on the UI thread.
• HyperAnimatedWidget controller lifecycle hardened — switched from SingleTickerProviderStateMixin to TickerProviderStateMixin (the previous mixin asserted on the second createTicker() when didUpdateWidget recreated the controller after a prop change). Start delay now uses a retained Timer that is cancelled on didUpdateWidget / dispose, eliminating duplicate forward() calls in fast-rebuild scenarios (live editor typing).

Performance

• HtmlAdapter.extractCss regex fast-path — for inputs ≥ 32 KB or with no <style tag at all (the common Markdown/Delta case), extractCss now skips the full html5lib parse on the UI thread and uses a focused regex. Saves 50–300 ms on a 200 KB document on a mid-range Android.

Cross-package Polish

• MarkdownContentParser renamed to DefaultMarkdownParser — aligns with DefaultHtmlParser / DefaultCssParser. The old name remains as a @Deprecated typedef so existing callers compile; new code should use the new name.
• hyper_render_devtools now has tests + dev_dependencies block — UdtSerializer round-trip + truncation cap + register() idempotency. Previously the package shipped zero tests.
• hyper_render_math pubspec description normalised — replaced the YAML folded-scalar (>) form with a plain string for consistency with the other six packages.
• pubspec_publish_ready.yaml and scripts/prepare_publish.sh version sync — both now pin ^1.3.2, eliminating the previous 1.3.1/1.3.2 mismatch that would have failed dart pub publish --dry-run.

Tests

71 new tests added across 11 files covering every fix above: URL safety scheme blocklist (core), HTML adapter URL gate, CSS parser edge cases, markdown GFM (tables/task-lists/autolinks/code-fence/heading), highlight edge cases (malformed source, 5 KB load, every theme), clipboard filename sanitisation, UDT serializer shape + truncation, animation controller race / dispose, table cell fallback + total-cell cap, extractCss perf, ellipsis copy + selection clamp regressions. Full suite: 1764 passing, 0 failing.

---

1.3.1 - 2026-05-14

⚠️ Migration from 1.3.0

hyper_render_clipboard and hyper_render_math are no longer transitive dependencies of hyper_render. If you use either, add them explicitly:

dependencies:
  hyper_render: ^1.3.1
  hyper_render_clipboard: ^1.3.1   # only if you use SuperClipboardHandler
  hyper_render_math: ^1.3.1        # only if you use MathNodePlugin / LatexNodePlugin

✨ New CSS Properties

• list-style-type: All 11 marker types — disc, circle, square, decimal, decimal-leading-zero, lower-alpha, upper-alpha, lower-latin, upper-latin, lower-roman, upper-roman, none
• list-style-position: inside / outside
• list-style shorthand: parses type and position in any order
• background-repeat: repeat, repeat-x, repeat-y, no-repeat, space, round
• background-position: keyword (center, top left, etc.) and percentage values

🚀 Performance

• Selection rects cached: getSelectionRects() now called once per drag event (was 3×) — stored in _selectionRects field, eliminating redundant layout walks during selection drag
• Auto-scroll proportional speed: _autoScrollIfNearEdge scales 0–20 px/frame based on finger proximity to edge (was fixed 15 px/frame)
• HyperTeardropHandlePainter deduplicated: renamed, made public, and exported from hyper_render_core; duplicate implementation in the virtualized overlay removed

🐛 Bug Fixes

• Edge-to-edge images: width: 100% images now truly fill their container — no internal margin offset

🏗️ Build Fixes

• Decoupled native dependencies: hyper_render_clipboard and hyper_render_math removed from root hyper_render default dependencies — eliminates the compileSdk = 34 Gradle requirement for basic usage
• Removed outdated compileSdk workaround from example app's Android Gradle config

1.3.0 - 2026-05-03

✨ New Features

• New Plugin Package: hyper_render_math (packages/hyper_render_math): Added first-party support for mathematical formulas via LaTeX/MathML. It uses a custom HyperNodePlugin to render math content using the flutter_math_fork package. This milestone release consolidates all recent architectural improvements and bug fixes into a stable minor version.

🚀 Performance & Stability

• Test Coverage Optimization: Increased global test coverage to >85% with new comprehensive suites for parsers, adapters, and selection logic.
• Golden Test Alignment: Updated golden tests for consistent multi-platform rendering validation.
• Improved Widget Test Robustness: Updated find.byType(HyperRenderWidget) assertions to handle multiple instances in the tree caused by virtualization and float nesting.
• Paint() memory optimization: Replaced inline Paint() allocations in hot paint paths with reusable fields, reducing GC pressure during smooth scrolling.
• Incremental layout hash collision fix: Improved the fingerprinting of document sections to prevent cache collisions on duplicate content.

🐛 Bug Fixes

• Markdown CRLF normalisation: Content is now normalised to LF before splitting, fixing stray carriage-return characters in code blocks on Windows.
• Virtualized Heading Protection: Added guards to prevent virtualized sections from orphaning headings (Heading Widow/Orphan protection).
• Config & Scheme Propagation: Fixed issues where useMicrotaskParsing and allowedCustomSchemes were dropped during CSS-driven config rebuilds.
• Float Layout precision: Explicit CSS width and height are now strictly respected for non-image float elements.
• Selection logic refinement: Fixed edge cases for text selection across off-screen chunks in virtualized lists.
• Android & iOS Build compatibility: Modernized Gradle configuration and iOS project settings for better ARM64 simulator and modern SDK support.
• SVG Sanitization: Added an atomic SVG sanitization path to preserve structural elements while stripping dangerous attributes.
• Plugin Propagation: Ensured pluginRegistry is correctly passed to nested renderers inside floated containers.

1.2.2 - 2026-04-02

🐛 Bug Fixes

• Android build failure with modern compileSdk (example/android/build.gradle.kts): irondash_engine_context 0.5.5 was compiled against android-31 but its transitive androidx.fragment:1.7.1 dependency has minCompileSdk=34, causing AGP 8's checkAarMetadata to block the build. Added a subprojects { afterEvaluate { compileSdk = 35 } } override in the example's root Gradle file. README now documents the same one-line workaround for app-level projects. (#5)
• SVG invisible with sanitize: true (html_sanitizer.dart): <svg> was not in defaultAllowedTags so the sanitizer unwrapped it, destroying the SVG structure. Added an atomic SVG sanitization path that strips <script> and dangerous attributes while preserving all structural SVG elements (path, circle, g, use, etc.).
• selectable toggle ignored after build (hyper_viewer.dart): Toggling selectable from false → true never created VirtualizedSelectionController, and true → false never disposed it. Fixed in didUpdateWidget.
• Deep-link tap silently blocked (hyper_viewer.dart): _safeOnLinkTap only checked widget.allowedCustomSchemes but ignored renderConfig.extraLinkSchemes, causing deep-links registered via HyperRenderConfig to be silently dropped. Both sources are now consulted.
• CSS change didn't invalidate section cache (hyper_viewer.dart): _hashSection hashes only text content, so a customCss change that alters layout/appearance would incorrectly reuse cached sections. _sectionHashes is now reset whenever customCss changes in didUpdateWidget.
• Markdown/Delta virtualized/paged mode rendered as single section (hyper_viewer.dart): The sync fallback path wrapped the entire parsed document as one section, defeating virtualization. Added _splitIntoSections() to chunk Markdown/Delta documents at block boundaries, matching the HTML isolate path.
• renderConfig change only partially detected (hyper_viewer.dart): didUpdateWidget compared only virtualizationChunkSize instead of the full HyperRenderConfig. Now uses full value equality (available since the operator== fix) so any config change triggers a re-parse.
• CSS float class names not detected (html_adapter.dart): _containsFloatChild missed Bootstrap/Tailwind float class names (float-left, pull-right, alignleft, etc.), causing premature section splits after float-containing blocks. Common class patterns are now detected heuristically.

1.2.1 - 2026-03-31

🏗️ Maintenance

• Pub.dev compliance: Fixed internal dependency constraints to use version ranges instead of path dependencies in the published package.
• Virtualized screenshot description: Refined screenshot metadata in pubspec.yaml for better display on pub.dev.
• Metadata cleanup: Removed stale comments and aligned topics for better discovery.

1.2.0 - 2026-03-30

✨ New Features

• Multi-tier Plugin API (hyper_render_core): Third-party packages can now render arbitrary HTML tags as custom Flutter widgets via HyperNodePlugin / HyperPluginRegistry.

  • Block tier (isInline == false, default): widget takes full available width with CSS margins.
  • Inline tier (isInline == true): widget flows inside text lines; intrinsic size measured in performLayout via getMaxIntrinsicWidth / getMinIntrinsicHeight.
  • Register at startup: HyperPluginRegistry()..register(MyPlugin()) and pass to HyperViewer(pluginRegistry: ...).

• Dirty-flag incremental layout (hyper_viewer.dart): Only re-layout sections whose content changed. Each DocumentNode chunk is fingerprinted with Object.hashAll over child textContent; unchanged sections are reused on the next parse, and ValueKey(hash) on RepaintBoundary lets Flutter skip re-layout and repaint entirely. ~90 0x0p+0yout rebuild reduction for live-updating feeds.

• Paged mode (HyperRenderMode.paged): PageView.builder-based rendering, one document chunk per page. Suitable for e-book / epub / reader UIs.

  • Supply a HyperPageController for programmatic navigation (animateToPage, nextPage, previousPage, jumpToPage) and ValueNotifier<int> currentPage for reactive page indicators.

♿ Accessibility (WCAG 2.1 AA)

• Image alt-text semantic nodes (render_hyper_box_accessibility.dart): <img alt="…"> elements now produce a discrete SemanticsNode at the image's layout rect. Screen-reader users can navigate to images element-by-element (WCAG 1.1.1 Non-text Content). Previously alt text only appeared in the flat document-level label.
• aria-label on links honored (render_hyper_box_accessibility.dart): If an <a> element carries an aria-label attribute, that value is used as the link's semantic label instead of its text content (WCAG 4.1.2 Name, Role, Value).

🏗️ Refactor — Dead-code elimination

• Removed 31 duplicate files from root lib/src/ that were identical or outdated copies of the canonical implementations in packages/hyper_render_core. Root lib/src/ now contains only the 17 files that are genuinely unique to the root package (parsers, sanitizer, HyperViewer, virtualized selection, capture_extension).
• LazyImageQueue singleton deduplication: lib/src/core/lazy_image_queue.dart was a separate implementation that created a second LazyImageQueue.instance — meaning LazyImageQueue.instance.cancel() called from outside HyperViewer hit a different singleton than the one HyperViewer used internally. Root now re-exports LazyImageQueue directly from hyper_render_core (single shared instance).
• Added missing v1.2.0 symbols to root re-export: HyperRenderConfig, LazyImageQueue, HyperNodePlugin, HyperPluginRegistry, HyperPluginBuildContext, LoadingSkeleton, HyperErrorWidget, FloatCarryover are now all accessible from package:hyper_render.
• Consolidated double export: The redundant second export 'package:hyper_render_core' show HyperRenderConfig' line was folded into the main re-export block.

🐛 Bug Fixes

• Copy action produced empty clipboard (virtualized_selection_overlay.dart, hyper_selection_overlay.dart): The Listener.onPointerDown callback cleared the active selection before the Copy button's onPressed could fire, so Clipboard.setData received an empty string. Fixed by guarding clearSelection() behind a _showMenu / _showContextMenu check (matching the pattern already used in the non-virtualized overlay).

• Context menu outside hit-testable bounds (hyper_selection_overlay.dart, virtualized_selection_overlay.dart): When a selection was near the top of the widget the computed top for the Positioned menu went negative. Stack(clipBehavior: Clip.none) allows visual overflow but Flutter hit-testing is still bounded by the parent — the Copy button was unreachable. Fixed by clamping the top offset: .clamp(0.0, double.infinity).

• Scroll vs. text-selection conflict (render_hyper_box.dart): handleEvent(PointerMoveEvent) bypassed the gesture arena and fired on every pointer move, creating accidental selections during scrolling. Removed raw-event selection tracking and moved selection initiation to a LongPressGestureRecognizer at the widget layer — this correctly competes with the parent scroll view's VerticalDragGestureRecognizer, so a quick swipe scrolls while a 500 ms hold begins a text selection (matching iOS/Android native behaviour).

• Virtualized copy menu never appeared (virtualized_selection_overlay.dart): Per-chunk RenderHyperBox._selection was set by the old pointer-event tracking, but VirtualizedSelectionController (cross-chunk selection) was never populated, so hasSelection remained false and the menu was never shown. Fixed by routing the long-press start through VirtualizedSelectionController.startSelection().

• Selection Escape key fix (hyper_selection_overlay.dart): Escape key failed to clear selection because the internal FocusNode wasn't reliably focused after selection was established. Fixed by calling _focusNode.requestFocus() inside startSelectionAt.

• const lint fix (hyper_render_widget.dart): HyperPluginBuildContext instantiation changed to const to silence prefer_const_constructors.

---

1.1.4 - 2026-03-28

🐛 Bug Fixes

• display:none not respected in renderer (render_hyper_box_layout.dart): Added early-return guard in _tokenizeNode — elements with display:none no longer produce any layout fragments and are correctly hidden. Previously, elements styled with display:none (e.g. Wikipedia [edit] section links) were still rendered.

• <hr> rendered as line break (html_adapter.dart): <hr> now correctly returns a styled BlockNode with a top border (borderColor: #CCCCCC, borderWidth: 1px), matching browser behavior. Previously it was incorrectly treated identically to <br>.

• Whitespace-only space nodes dropped between inline elements (html_adapter.dart): Text nodes consisting only of horizontal spaces (e.g. " " between <b>text</b> <i>more</i>) were being silently dropped by .trim().isEmpty, causing missing word-separating spaces. Fixed to only drop nodes that contain newlines (structural indentation whitespace), not pure-space nodes.

• TextPainter cache hash collision (render_hyper_box.dart): The _LruCache<int, TextPainter> key was computed with Object.hash() which can collide for large documents with many distinct text styles, leading to wrong text metrics and subtle layout glitches. Replaced with a new _TextPainterKey class using full value equality over all 9 style fields.

---

1.0.0 - 2026-03-01

First stable release. Core features, plugin architecture, and cross-platform support are production-ready.