[JFWooten4]

Summary

Add More PDF tools → Automatically copy selected text, a persistent, off-by-default preference for the PDF viewer.

• Disabled: PDF text selection only displays its highlight; the clipboard stays untouched until an explicit Copy action.
• Enabled: after a primary-button text selection finishes inside the PDF text layer, automatically trigger the same browser Copy action used by Ctrl/Cmd+C. This preserves the selected highlight while honoring the existing Copy selection as Markdown, tagged-paragraph reflow, and footnote behavior introduced in 🖌️ Add opt-in Markdown copying for PDF selections #175.
• Ignore toolbar and external-page selections, secondary-button gestures, collapsed or empty selections, canceled drags, and focus-loss interruptions.
• If the native Copy command is denied, fall back to clipboard text writing using the selected text (and existing formatting where available); report failure if writing also fails.

Tests

Added tests/auto-copy-selection.test.mjs and registered it in npm test to cover default-off behavior, valid selected PDF text, foreign or secondary-button selection, collapsed or out-of-layer selection, pointer cancellation, blur, and failed-command fallback.

Verification: Compared branch against main: one nonempty commit, with exactly the seven intended file changes and no unrelated modifications. Browser/runtime tests were not executed locally in this environment; CI and interactive manual verification remain necessary.

Manual verification

1. Select words with the toggle off; the highlight should appear without changing the clipboard.
2. Enable the toggle and drag-select words (including the end of a line); paste into another application. The copied text should correspond to the selected text and the visual selection should stay highlighted.
3. With Markdown copying enabled, repeat on italic/bold passages and passages with footnotes; paste to confirm the normal Copy formatting is reused.
4. Confirm selections in toolbar fields and right-click gestures do not overwrite the clipboard.