v1.4.0

Added

• Add transactional image loading, Fabric image creation timeout handling, and broader regression coverage for failed loads, history errors, crop undo, animation disposal, and mask ID restoration.
• Add demo error feedback for failed image loads and direct event binding for the Base64 export action.

Changed

• Export canvas regions directly through Fabric region export options to reduce peak memory usage and avoid asynchronous exposure of export-only mask styles.
• Run independent esbuild outputs in parallel and include docs/js/**/*.js in lint coverage.
• Preserve alpha-capable PNG/WebP formats during downsampling unless an explicit downsample MIME type is configured.
• Preserve developer-defined canvas CSS sizing and reuse the last visible container viewport when layout is temporarily hidden.

Fixed

• Fix history queue rejection handling, history overflow indexing, and async command execution ordering.
• Fix animation cancellation during disposal and restore rotation origins on animation failure paths.
• Fix loadImage() rollback for placeholder visibility, overflow, image state, and canvas state after load failures.
• Fix duplicate mask IDs after merge, undo, and new mask creation.
• Fix shared-parent placeholder layouts, Bootstrap visibility restoration, stale crop handlers, and crop preservation for rotated masks.
• Fix public destructive/export operations so they reject or no-op clearly while animations are running.
• Fix file loading for empty MIME types with image file extensions and reset file inputs after load attempts.
• Fix demo null tolerance, dragleave flicker, release tag checks, mask list selection targeting, and export conversion failures when a 2D context is unavailable.