fix(mobile): restore PDF text selection - #625
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- Fix canvas DPI scaling for Retina displays (outputScale transform) - Rewrite getSelectedText with geometric sorting for reliable extraction - Dynamic endOfContent marker positioning for accurate selection bounds - Custom copy handler using DOM-based text extraction - Add letter-spacing/word-spacing normalization in text layer CSS - Disable annotation layer pointer events during selection - Replace <br> with newlines in range text extraction - Proper event cleanup via AbortController
Mobile PDF text selection was broken because the committed reader.html bundle (built 2026-07-04, 22 days before the macOS fix 9c601b8) embedded pdfjs 4.10.38 with the buggy documentElement transform = scale(1/dpr) that misplaces text selection. The desktop fix never reached mobile. Root causes (all verified): 1. Stale committed bundle: reader.html had a hardcoded build id and the old scale(1/devicePixelRatio) rendering hack; rebuilt from current source. 2. The reader template injected EPUB reflow styles (font-size/font-family/ line-height/color:inherit !important) into PDF fixed-layout iframes, breaking the pdf.js TextLayer glyph sizing and exposing its transparent glyphs. Desktop already guards this (FoliateViewer.tsx); mobile lacked it. 3. Missing readest mobile workarounds: iOS accessibility font-size scaling (getFontScale) and the WKWebView ~2GB memory ceiling (getRenderDpr). Changes: - foliate-js/pdf.js: add getFontScale / isMobileWebView / getRenderDpr with MAX_RENDER_DPR=2 and MAX_CANVAS_PIXELS=2048*1536; render() uses renderDpr (desktop isMobileWebView()=false -> real dpr, zero regression); divide fontScale out of --text-scale-factor (glyph lever only); annotation linkService getAnchorUrl. - reader.template.html: buildFixedLayoutStyles() safe block + isFixedLayout guards in applySettings/applyDocStyles/setThemeColors; applyDocStyles syncs the freshly computed fixedLayoutStyles so a stale lastRendererStyles (never reset in openBook) can't leak EPUB reflow styles into the first PDF page on an EPUB->PDF switch in the same WebView. - build-reader.js: stamp a real build id (git sha + timestamp) so stale bundles are detectable via the RN [ReaderBuild] debug message. - reader.html: rebuilt with pdfjs 5.5.207 + all workarounds. - pdfjs-dist unified to ^5.5.207 everywhere; delete npm leftover foliate-js/package-lock.json (pinned 4.7.76); remove dead @pdfjs vite alias and copyPDFJS rollup plugin. - docs/mobile-pdf-text-selection-fix.md: root-cause analysis, solution, rationale, and independent review findings.
…nt build id - pdf.js: reset the inline --text-scale-factor and reapply the OS font-size correction before TextLayer.render() so a scale left by a previous accessibility-font-size render never leaks into the next page. - build-reader.js: replace git-sha+timestamp build id with a deterministic SHA-256 of the placeholder-stripped HTML, so identical source and dependencies produce byte-identical reader.html and a stale bundle is detectable without depending on a commit SHA. - docs: sync the mobile PDF text selection fix document with the above.
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pnpm --dir packages/app-expo build:reader