TabMark 1.2.1
Fixed a restore regression where only one tab could open instead of restoring the full saved window.
Restored tabs are now created explicitly in order to preserve all saved entries.
Added a regression check for multi-tab restore behavior.
Verified with the project test suite: node tests/tabs.test.js passed.

Atomic save replacement with staging and rollback protection.
Metadata v2 associates groups with bookmark IDs.
Sync/import fallback uses URL, title, and duplicate occurrence.
Bookmark reordering no longer changes group assignments.
Legacy metadata v1 and flat saves remain supported.
Partial restore windows are removed after failure.
Concurrent button operations are prevented.
Errors, warnings, and success messages appear in the popup.
Unsupported tabs remain saved as ordinary bookmarks with a warning.
Correct metadata identification prevents page-title collisions.
Accessible buttons, labels, focus styling, dialog semantics, and reduced-motion support.
Added the required no-data-collection declaration.

Added delete confirmation dialog.