You'll noticeTier: how much it should matter to you
1Useful: my rating, 1 to 5
1Signal: worth watching, 1 to 5
ElsewhereArea: what it touches
ImprovementsKind: in v2.1.290,
ImprovementsSection of the release
Unclear The overall effect on what the sandbox allows or blocks is not clear.
What
On WSL (Windows Subsystem for Linux, which runs Linux inside Windows), Claude Code now finds your Windows drives by reading /proc/self/mountinfo instead of /proc/self/mounts. Its error and status messages now name the new file.
The sandbox is a set of limits on which files and network addresses the commands Claude runs can reach. The code that builds those limits was restructured:
Paths blocked from reading (denyRead) are now always processed, rather than only in some cases
Paths to credential files are worked out in a different way
Why
This touches how Claude Code serves cloud sessions on WSL and which files the sandbox lets commands read. If file access inside the sandbox behaves differently after updating, this rework is a likely place to look.
How sure we are
Something disagreesSomething we can check disagrees with this entry, or the writer said they could not settle it.
The writer flagged doubtThe overall effect on what the sandbox allows or blocks is not clear.
Anthropic's release notes agreeFixed a project CLAUDE.md, rule or AGENTS.md symlinked outside the working directories loading under…
