Summary

• Removes e.stopPropagation() from handleEdgeDrop and handleCenterDrop in PaneWrapper.tsx
• Adds a safety-net useEffect that clears dragActive whenever a workspace becomes active

Root cause

In React 17+, synthetic event handlers fire at the React root container (not document). Calling stopPropagation() inside handleEdgeDrop / handleCenterDrop prevented the native drop event from bubbling past the React root to document. Every other PaneWrapper listens at the document level for drop to reset dragActive = false — they never received the event and stayed permanently stuck with dragActive = true.

After any tab drag-to-split, all panes in all workspaces had dragActive = true. Switching to another workspace then rendered the drop zone overlay (the "highlighted sections") over every terminal with pointer-events: auto, blocking all mouse interaction.

Fix

1. Remove stopPropagation() from both drop handlers so the native drop event propagates to document and all PaneWrapper instances reset correctly.
2. Safety-net useEffect — clears dragActive when isWorkspaceActive transitions to true, covering the edge case where dragend fires on a detached DOM element (e.g. when splitAndMoveSurface removes the source tab from the tree before dragend fires) and never reaches document.

Test plan

• Drag a terminal tab to an edge drop zone to split the pane
• Switch to another workspace — no highlighted overlay sections should appear, terminal clicks should work normally
• Drag a terminal tab to the center drop zone to merge panes, then switch workspace — same result
• Verify normal tab reordering (drag within the tab bar) still works

🤖 Generated with Claude Code