What
Claude Code can now automatically detect your terminal's light or dark theme and match it, using the "Auto (match terminal)" theme option.
Details
- A new system theme watcher uses OSC 11 terminal escape sequences to query the terminal's background color
- The detected luminance determines whether the terminal is "light" or "dark"
- Supports multiplexers (tmux, screen) with DCS passthrough and fallback detection
- Theme changes are detected dynamically — if you switch your terminal's theme, Claude Code follows
- The "Auto (match terminal)" option is now available in the theme picker
Evidence
System theme detection via OSC 11 in Wh_() at line ~185609 (search for "systemTheme: OSC 11") — 0 occurrences in v2.1.110, 2 in v2.1.111
Strings lifted out of the shipped bundle, so the claim above can be checked against them.