Plan mode hangs with pause on SteamOS (Konsole) with multiple MCP servers

Plan mode consistently hangs on SteamOS (Steam Deck) after ~30s of thinking. The ⏸ pause symbol appears in the status bar next to "plan mode on", and the UI becomes completely unresponsive. No response is ever rendered.

This does not occur on WSL2 with identical configuration (same MCP servers, same settings, same model).

Environment

• Claude Code version: 2.1.63 (via cc-mirror)
• OS: SteamOS 3.x (Arch-based Linux)
• Terminal: Konsole (KDE)
• TERM: xterm-256color
• COLORTERM: truecolor
• TERM_PROGRAM: (unset)
• Model: Opus 4.6

Configuration

• 6 MCP servers active (Serena, GitHub, Google Workspace, Twitter, Diagram Bridge, Memory)
• Custom statusLine (shell command, completes in ~47ms — not the cause)
• SessionStart/SessionEnd hooks
• 11 enabled plugins (sentry-skills, superpowers, trailofbits suite)
• Feature flag tengu_plan_mode_interview_phase: False

Reproduction Steps

1. Start Claude Code with the above MCP configuration
2. Enter plan mode (shift+tab or via EnterPlanMode tool)
3. Send any message
4. Observe: thinking indicator appears for ~30s
5. ⏸ pause symbol appears in status bar
6. UI becomes unresponsive — no output rendered, no way to interact

Expected Behavior

Plan mode should render the planning response and allow interaction.

Hypothesis

The ⏸ symbol suggests Claude Code is waiting for user input (likely a permission prompt for an MCP tool call) that cannot render because plan mode's UI state takes over the input area. This creates a deadlock — the permission prompt needs user input, but the UI can't show the prompt.

This would explain why it works on WSL (different terminal capabilities / TERM_PROGRAM set) but not on SteamOS/Konsole (TERM_PROGRAM unset).

Workaround

Avoid plan mode. Describe the approach in conversation and ask for feedback instead.