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DisclaimerUnofficial, and not affiliated with Anthropic. Nearly all of this is read straight out of what ships: npm bundles, captured prompts, published docs. Anthropic's own notes go in verbatim, marked as theirs. The rest is my reading, and every entry carries the strings behind it. If one looks wrong, vote it down and say why.

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Claude Code v2.1.8

11 entries read diff v2.1.7 → v2.1.8 Markdown

This release adds the /fork command for creating conversation forks, extends browser extension support beyond Chrome to include Brave, Edge, Arc, Chromium, Vivaldi, and Opera, and introduces macOS sleep prevention during long operations. The "ultrathink" keyword is now deprecated since thinking budget is max by default.

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Changesopen

/fork Command#

What

Create a fork of the current conversation at any point, branching off into a separate session while preserving the original context.

Usage
/fork              # Fork with auto-generated name
/fork my-branch    # Fork with custom name
Details
  • Creates a complete copy of the conversation up to the current point
  • Automatically switches you to the new forked session
  • Preserves all message history, attachments, and context
  • Emits telemetry event tengu_conversation_forked
  • Use /resume to switch between original and forked sessions
Evidence

cK7 at line 489820 (name: "fork", description: "Create a fork of the current conversation at this point")

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Related

Other releases about the same thing. Found by shared names or similar wording; neither means one caused the other.

Multi-Browser Extension Support#

What

The "Claude in Chrome" browser extension now supports multiple Chromium-based browsers beyond just Google Chrome.

Details
  • Newly supported browsers: Brave, Microsoft Edge, Arc, Chromium, Vivaldi, Opera
  • Auto-detects installed browsers and configures native messaging hosts for each
  • Registers appropriate Windows registry keys for each browser
  • Cross-platform support (macOS, Linux, Windows)
Evidence

txA at line 295966 (browser config object with "brave", "arc", "edge", "chromium", "vivaldi", "opera" entries and NativeMessagingHosts paths)

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Related

Other releases about the same thing. Found by shared names or similar wording; neither means one caused the other.

macOS Sleep Prevention#

What

Claude Code now automatically prevents macOS from sleeping during long-running operations.

Usage: Automatic—no user action required.

Details
  • Uses macOS caffeinate -i command to prevent idle sleep
  • Active only during operations that need it (reference-counted)
  • Automatically restarts caffeinate every 4 minutes to maintain prevention during very long tasks
  • Properly cleans up on session exit
  • Only applies to macOS; no effect on other platforms
Evidence

OW9() at line 517291 (caffeinate, -i, -t, "Started caffeinate to prevent sleep")

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Plan Mode Interview Skip#

What

In plan mode, you can now skip the AskUserQuestion interview and jump straight to planning.

Details
  • When answering plan mode questions, a new option appears: "Skip interview and plan immediately"
  • Also adds "Chat about this" option for discussing questions with Claude
  • Navigate between options using arrow keys
  • Useful when you want Claude to proceed without answering all clarifying questions
Evidence

kD9() at line 521459 ("Skip interview and plan immediately", "Chat about this")

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

.claude Folder Session Permissions#

What

A new permission scope for allowing Claude to edit its own configuration files within .claude/ directories.

Details
  • When Claude requests to edit files in .claude/, a new option appears: "Yes, and allow Claude to edit its own settings for this session"
  • Grants session-scoped permission for the /.claude/** glob pattern
  • Streamlines workflows where Claude needs to update its own configuration
Evidence

GrA at line 96077 ("/.claude/**"), LN7() at line 517637 (scope: "claude-folder")

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Context Microcompaction Boundaries#

What

New internal infrastructure for tracking context compression events in long conversations.

Details
  • Adds microcompact_boundary system message type
  • Tracks metadata about compaction: trigger, tokens saved, compacted tool IDs
  • Used internally for session memory management
  • No direct user interaction required
Evidence

Uv2() at line 430955 (subtype: "microcompact_boundary", content: "Context microcompacted")

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Related

Other releases about the same thing. Found by shared names or similar wording; neither means one caused the other.

tmux Integration Improvements#

Adds platform-specific installation instructions when tmux is not found:

  • macOS: brew install tmux
  • Linux: sudo apt install tmux or sudo dnf install tmux
  • Windows: Suggests WSL or Cygwin
Evidence

ZI9() at line 513876 ("Install tmux with: brew install tmux")

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Related

Other releases about the same thing. Found by shared names or similar wording; neither means one caused the other.

Settings Validation for Cleanup#

When settings have validation errors but cleanupPeriodDays is explicitly set, cleanup is now skipped with a clear warning message rather than potentially misbehaving.

Evidence

ww9() at line 540061 ("Skipping cleanup: settings have validation errors but cleanupPeriodDays was explicitly set")

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Related

Other releases about the same thing. Found by shared names or similar wording; neither means one caused the other.

OAuth Metadata Discovery#

MCP OAuth connections now attempt to auto-discover OAuth metadata from the server, improving compatibility with OAuth providers.

Evidence

g92() at line 296348 ("Set OAuth metadata from server discovery")

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

File Download for API Sessions#

Adds file download infrastructure for SDK/API sessions with retries and parallel download support.

Evidence

HR7() at line 537150 (files-api-2025-04-14, "/v1/files/${A}/content")

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

2 entries

Bug Fixesopen

#

  • Fixed variable expansion detection to properly recognize both $VAR and %VAR% patterns (Xh() at line 501011)
  • Internal telemetry function renames for consistency (multiple functions)

Related

Other releases about the same thing. Found by shared names or similar wording; neither means one caused the other.

Ultrathink Keyword Deprecated#

What

The ultrathink keyword no longer has any effect.

Details
  • Previous behavior: typing "ultrathink" in a message would enable extended thinking
  • New behavior: Thinking budget is now max by default for all messages
  • Users may see a tip: "Ultrathink no longer does anything. Thinking budget is now max by default."
  • The regex pattern still exists but the parsing/detection logic has been removed
Evidence

Tip at line 528403 ("ultrathink-deprecated", "Ultrathink no longer does anything. Thinking budget is now max by default.")

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Verbatim
No official entry

Not individually listed upstream

v2.1.8 does not have its own entry in Anthropic’s official changelog, because prerelease builds are often folded into a neighbouring release. Browse the full changelog for the closest official notes. Everything else on this page came out of the bundle instead, which is why the two lists don't match.

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