Claude Code v2.1.27

Released Jan 30, 2026 (7 months ago).

"References this build" means the issue body mentions running 2.1.27 (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 v2.1.27

Ranked by community engagement (reactions and comments).

• [BUG] Critical memory regression in 2.1.27 - OOM crash on simple input
  Resolved 💬 65 👍 92 #22042
• [BUG] Copy/paste from terminal has new lines instead of wrapping properly
  Open 💬 15 👍 75 #22073
• BUG: classifyHandoffIfNeeded is not defined - SubagentStop hook failure
  Resolved 💬 26 👍 48 #22087
• [BUG] Claude Code 2.1.27 freezes after first message - regression from 2.1.25
  Resolved 💬 24 👍 47 #22103
• v2.1.27 hangs at 100% CPU after first response (v2.1.25 works)
  Resolved 💬 15 👍 27 #22158
• CLI hangs at 99% CPU on startup with large session .jsonl files
  Resolved 💬 12 👍 23 #22041
• [BUG] TUI copy/paste includes trailing whitespace padding and ANSI escapes — Ink renderer uses space-padding instead of \x1b[K
  Open 💬 4 👍 23 #23014
• [BUG] Bug Report - Claude Code 2.1.27 hangs on startup
  Resolved 💬 9 👍 19 #22116
• [BUG] Past Conversations not showing in VSCode extension despite valid sessions-index.json
  Open 💬 13 👍 15 #22215
• [BUG] Claude enters plan mode automatically without waiting for user approval
  Open 💬 7 👍 15 #22220
• [BUG] CLAUDE_CODE_ADDITIONAL_DIRECTORIES_CLAUDE_MD not loading CLAUDE.md if additionalDirectories is specified in settings.json
  Open 💬 8 👍 12 #22583
• v2.1.23+ causes 100% CPU hang with multiple parallel instances and hooks
  Resolved 💬 9 👍 10 #22172
• Scroll back + Color bleaching + Memory leak fix -- npm i -g claudefix --- Cons: Plugs myself and runs an ad, makes claude immutable so it stays locked --- Slowly adding more festures to ennhance UX, youre a bot if youre bitching about safety in the comments.. Linux only
  Resolved 💬 24 👍 3 #22546
• [BUG] Edit/Write tools bypass permissions.ask rules (regression of #11226)
  Resolved 💬 9 👍 7 #22055
• Sessions not added to sessions-index.json, invisible to resume
  Resolved 💬 8 👍 7 #22205
• [BUG] v2.1.27: --resume and --continue freeze on macOS (regression from 2.1.26)
  Resolved 💬 8 👍 6 #22190
• [BUG] Claude Code 2.1.27 spikes to 100% CPU and becomes unresponsive; .claudeignore not respected
  Resolved 💬 6 👍 6 #22198
• [BUG] `argument-hint` YAML frontmatter with brackets causes React error #31 and unrecoverable TUI hang
  Resolved 💬 3 👍 6 #22161
• [Bug] Extreme memory usage peak (13GB) in v2.1.27 with plan mode and screenshots
  Resolved 💬 3 👍 5 #22183
• [Bug] Context indicator wraps character-by-character in narrow terminals
  Resolved 💬 5 👍 4 #22222
• /plugin command causes 100% CPU freeze (v2.1.27)
  Resolved 💬 10 👍 2 #22077
• 2.1.27: 100% CPU infinite loop on --continue / --resume / session listing
  Resolved 💬 4 👍 4 #22061
• Session resume freezes with 100% CPU due to redundant progress events in session files
  Resolved 💬 9 👍 2 #22149
• [BUG] Session cannot be resumed - hangs on load (2.1.27)
  Resolved 💬 6 👍 3 #22132
• [BUG] Memory leak: API clients created repeatedly instead of reused (8-9 GB memory usage)
  Resolved 💬 5 👍 3 #22162
• v2.1.27 regression: Event loop stuck (CPU 90%+ spin) on startup when stale lock exists or another session is running
  Resolved 💬 6 👍 2 #22242
• [BUG] Regression in 2.1.27: Infinite CPU loop on project startup
  Resolved 💬 3 👍 3 #22057
• [BUG] v2.1.27 VSCode extension has critical memory leak
  Resolved 💬 5 👍 2 #22716
• Session metadata corrupted on /exit - loses conversation context on resume
  Resolved 💬 4 👍 2 #22347
• [Bug] CPU spinning when idle or blocked on I/O
  Resolved 💬 4 👍 2 #22256

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