Claude Code v2.1.21

Released Jan 28, 2026 (7 months ago).

"References this build" means the issue body mentions running 2.1.21 (from the bug-report template). It reflects report volume, not a proven defect count — an issue may mention a version without being caused by it. First-party data from the anthropics/claude-code tracker.

Top issues reported on v2.1.21

Ranked by community engagement (reactions and comments).

• [BUG] "operation not permitted: /tmp/claude-501/cwd-*" error on macOS in sandbox mode
  Resolved 💬 8 👍 29 #21654
• 🚨 CRITICAL: Memory leak causes freeze after 20+ minutes (15GB RAM consumption)
  Open 💬 9 👍 12 #21378
• Chrome extension native host crashes on Windows (Bun v1.3.5 panic)
  Resolved 💬 5 👍 6 #21418
• [BUG] Error: Error during compaction: Error: Conversation too long. Press esc twice to go up a few messages and try again.
  Resolved 💬 7 👍 5 #22051
• [DOCS] VS Code extension settings table missing usePythonEnvironment setting
  Resolved 💬 22 #21373
• `/ide` command fails with "onInstall is not defined" error
  Resolved 💬 11 👍 2 #21389
• Auto mode's Bash-first steering reverses 2.1.21 and 2.1.31, which shipped the opposite as a fix
  Open 💬 3 👍 3 #89731
• [BUG] Authentication fails with 403 error when using Claude extension via SSH remote connection
  Resolved 💬 3 👍 2 #21914
• Claude in Chrome native host crashes on Windows with Bun assertion failure
  Resolved 💬 3 👍 1 #21381
• [BUG] LSP plugin (vtsls@claude-code-lsps) not available in VSCode extension
  Resolved 💬 3 👍 1 #21374
• [Feature Request] Add token usage tracking and optimisation to reduce API consumption.
  Resolved 💬 3 #45757
• [BUG] Error: Conversation too long.
  Resolved 💬 3 #23469
• [BUG] IDE detection fails for remote cursor-server (SSH/Remote) - only matches desktop app process names
  Resolved 💬 3 #22494
• [BUG] Task list ID not inherited when transitioning from plan mode to execution
  Resolved 💬 3 #21807
• [Bug] Thai Language in Claude CLI
  Resolved 💬 3 #21407
• [Bug] Agent loops infinitely and incorrectly reports fixes despite persistent errors in logs
  Resolved 💬 3 #21401
• [BUG] "Chat about this" on AskUserQuestion sends is_error: true rejection — discards all answers, model plows ahead
  Resolved 💬 2 #33511
• [BUG] Authentication fails with 403 error when using Claude extension via SSH remote connection
  Resolved 💬 2 #21904
• [Bug] Anthropic API 400 errors from oversized screenshot payloads terminate conversation without recovery
  Resolved 💬 2 #21572
• Skills Load Successfully But Explicit Instructions Are Ignored (Regression)
  Resolved 💬 2 #21376
• [Windows] Bun console window appears when starting Claude Code
  Resolved 💬 2 #21375
• [BUG] Jetbrains Webstorm terminal bug
  Open 💬 0 #80107

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