[macOS][Computer History] Accessibility traversal repeatedly freezes IntelliJ IDEA Git Log for 10–13 seconds

What version of the Codex App are you using (From “About Codex” dialog)?

• ChatGPT/Codex Desktop: 26.810.52044 (build 6662)
• Computer Use service: 26.812.1000717 (build 1000717)

What subscription do you have?

Not included; this appears to be a local macOS Desktop / Computer History performance bug.

What platform is your computer?

• macOS 26.5.2 (25F84)
• Apple Silicon, 16 GB RAM
• IntelliJ IDEA 2026.2.1 (IU-262.9437.185), ARM64, JetBrains Runtime 25.0.3

What issue are you seeing?

With Computer History enabled, IntelliJ IDEA became unresponsive for 10–13 seconds at a time while its Git Log table was visible.

During one observed interval (2026-08-16 21:49:19–21:51:28 local time):

• IntelliJ produced 8 UI-freeze reports, each lasting 10–13 seconds.
• IntelliJ logged macOS sun.lwawt.macosx.CAccessibility timeouts during 89 distinct seconds.
• The macOS unified log contained 715 AccessibilitySupport.UIElementError entries from SkyComputerUseService.
• SkyComputerUseService used approximately 71–83% CPU in spot samples.
• 5 live SkyComputerUseClient computer-history mcp processes were observed.

The repeated IntelliJ EDT stack was:

sun.lwawt.macosx.CAccessibility._addChildren
  -> JBTable$AccessibleJBTable$AccessibleJBTableCell.getCurrentComponent
  -> JTable.getValueAt
  -> GraphTableModel.getValueAt
  -> Commit.getValue
  -> GraphTableModel.getPrintElements
  -> PrintElementGeneratorImpl.getPrintElements
  -> EdgesInRowGenerator.getEdgesInRow

This indicates that accessibility-tree enumeration is forcing IntelliJ to materialize Git graph table cells on its UI thread. The timing and error volume correlate with Computer History's accessibility collection.

IDE indexing, memory pressure, swap activity, and an out-of-memory condition were checked and did not explain these repeated 10–13 second freezes.

What steps can reproduce the bug?

This reproduced in the observed session with the following setup:

1. Enable Computer History in ChatGPT/Codex Desktop.
2. Open a large multi-module project in IntelliJ IDEA 2026.2.1.
3. Open Git > Log and leave the Git Log table visible.
4. Launch or actively use Codex Desktop while Computer History collection is running.
5. Observe periodic IntelliJ UI freezes.
6. Inspect IntelliJ freeze dumps for the CAccessibility -> AccessibleJBTable -> GraphTableModel chain and unified logs for SkyComputerUseService accessibility errors.

I have not yet completed a controlled A/B run after excluding IntelliJ from Computer History, so the workaround is not claimed as verified.

What is the expected behavior?

Computer History should collect accessibility events without recursively or repeatedly materializing expensive virtualized table contents on the target application's UI thread.

In particular, the Computer Use service should:

• throttle, cache, or bound accessibility-tree traversal for large tables;
• avoid repeatedly querying inaccessible/stale UI elements;
• deduplicate or otherwise bound concurrent computer-history mcp clients;
• avoid making another application unresponsive during background collection.

Additional information

Potentially related but not an exact duplicate:

• #38562 — Computer History causes periodic WindowServer ping timeouts and UI hitching.
• #25744 — accumulated Computer Use/MCP helpers and macOS stalls.
• #38455 — repeated Computer Use workers and high resource use.

The distinguishing evidence here is the target application's exact accessibility stack: CAccessibility._addChildren traversing IntelliJ's Git Log JBTable and forcing Git graph computation on the EDT.

No raw logs, session transcripts, project names, workspace paths, hostnames, or other local identifiers are attached. I can provide a redacted IntelliJ freeze report and a sanitized unified-log excerpt if maintainers need them.

Start with the reported CAccessibility._addChildren → AccessibleJBTable → GraphTableModel stack and reproduce the setup using IntelliJ IDEA Git Log with Computer History enabled. Inspect IntelliJ freeze dumps and macOS unified logs for accessibility traversal, timeouts, and concurrent computer-history mcp clients. Done means background collection no longer causes repeated long UI freezes, with the behavior verified in a controlled comparison.