[Danielku15]

Note

AI-authored disclosure (alphatab-ai-authored-v1)

Portions of this content were authored by an AI agent. The agent has read
AGENTS.md and the human submitter accepts responsibility for
compliance with the rules in that document.

Issues

No issue: 1.9.0 release preparation by the maintainer (release notes and website content). The maintainer asked for the Capella importer fix to go into this PR directly, as a minimal fix to make Capella import usable again; full Capella support is planned for 1.10.0.

Proposed changes

1.9.0 release notes (website/docs/releases/release1_9.mdx)

The notes did not cover the PRs merged since they were last updated:

• Performance (perf(rendering): rework the layout flow so resizes match fresh renders at half the time and memory #2997, perf(rendering): improve render performance #2751): new section. A resize now gives the same layout as a fresh render. Measurements against 1.8.4 and on a dense test score. Less work between page, worker and player: the score sent as one MessagePack buffer, resizes coalesced, partials far out of view release their DOM, MIDI generated once, player.positionUpdateIntervalInMilliseconds.
• Bundlers (feat: website in the monorepo on Rspack, with a shared alphaTab core for webpack, Rspack, Vite and Turbopack #2998): the existing sections link the PR. New items: webpack webWorkers: false, the plugin reports an error instead of hanging, the Vite worker and worklet chunks are no longer manifest entries, the minified builds define Ottavia._8va and the other enum members starting with an underscore again.
• Website (feat: website in the monorepo on Rspack, with a shared alphaTab core for webpack, Rspack, Vite and Turbopack #2998): new section on the landing page, Playground, feature catalog and reworked docs, and the move into website/.
• Release hardening (1.9.0 hardening: fix release-review findings across rendering, importers, player and packaging #2990): new section, grouped by area. Items the notes already covered are not repeated.
• Smaller fixes: fix(player): keep sync point times exact to avoid drift on non-integer tempos #2960, fix(importer): reject malformed GPX containers instead of looping forever #2991, fix(rendering): draw triplet feel once per bar and capo once per staff #2992, fix(rendering): compute beaming bounds for beats without notes #2993, fix(synth): let a local initialAttenuation replace the global zone value #2994, fix(midi): fade via expression and restore it with the voice's next note #2995 and fix(importer): apply MusicXML dynamics per part and show them only where written #2996, plus the model, JSON and platform fixes from perf(rendering): rework the layout flow so resizes match fresh renders at half the time and memory #2997, each crediting its reporter.
• Upgrade notes: page and worker must load the same version, coalesced resizes, position update interval, LogLevel.Trace, fades now use CC 11 in the generated MIDI, millisecond values keep their decimals, [Obsolete]/@Deprecated on deprecated members in C# and Kotlin, SVG output differences, npm provenance (ci: publish npm packages via trusted publishing, stage releases, add dry_run #2959).

All internal links and anchors were checked against next.alphatab.net: 104 pages and 73 anchors. The check rules out the host's fallback page, which is served with HTTP 200. PR, commit and user links were checked against GitHub.

Capella import (CapellaParser.ts)

Every .capx file failed with "No compatible importer found for file", in 1.8.4 too. The parser called Beat.updateDurations() before the beat was added to its voice and before its notes were read, so the full-bar rest check (Beat.isFullBarRest) dereferenced the missing voice. Chords now compute their duration after their notes are parsed, rests after they are added to their voice. CapellaImporter.test.ts is the first Capella test: a grand-staff file with lyrics, and inline CapXML with whole notes, full-bar rests and a half-bar rest. Both tests fail without the fix.

Landing page demos

The file tabs are there to show alphaTab loading different formats, but two of them loaded Guitar Pro files:

• prelude.musicxml now loads Bach_Prelude_BWV999.musicxml: the same four bars as Bach_Prelude_BWV999.gp, as one guitar part with a treble-8vb notation staff and a TAB staff. It validates against the MusicXML 4.0 schema. Imported, it matches the .gp in every pitch, duration, tie, string and fret.
• The former etude.capx tab (which loaded Drums.gp5) is now twinkle.capx and loads twinkle-mozart.capx: the K. 265 theme from twinkle-mozart.musicxml on a piano grand staff with lyrics. It validates against the CapXML 3.0.3 schema; the newer official schemas contain errors and do not compile. The Capella feature page loads it too, instead of a Guitar Pro file.

Both pieces are public domain.

Landing page content

• The showcase data no longer carries the outreach consent markers and their TODO comments.
• The platforms card no longer announces iOS.

Verification

• CapellaImporter.test.ts passes. The full suite and the C# and Kotlin tests were not run locally.
• The site typechecks, and the changed MDX pages compile.
• Both new demo files were imported and rendered with alphaTab and compared visually with their source files.

Checklist

• I consent that this change becomes part of alphaTab under its current or any future open source license
• This PR is linked to an accepted issue (see above)
• Changes are implemented
• New tests were added
• I have read AGENTS.md if an AI helped draft any part of this PR

AI authorship disclosure

• No AI agent authored any part of this PR (description, code, tests, or commit messages)
• An AI agent contributed to this PR. The AI-authored disclosure block
  (alphatab-ai-authored-v1) is present at the top of this body, and I have
  personally reviewed every change and can explain each one

Further details

• This is a breaking change
• Docs / release notes updated in website/