[BUG] VS Code extension: input field freezes (blinking cursor, no text entry) with multiple sessions open, tabs flicker rapidly

Environment

• Claude Code version: 2.1.195
• VS Code version: 1.127.0
• OS: Windows 11

Bug description

When multiple Claude Code sessions (tabs) are open in the VS Code extension at the same time, the text input field sometimes stops accepting input — the cursor keeps blinking but typed characters don't appear. When this happens, the currently selected tab appears to switch rapidly/flicker between tabs.

Steps to reproduce

1. Open two or more Claude Code sessions as separate tabs in VS Code
2. Continue working across tabs for a while
3. At some point, the input field in one tab stops accepting keystrokes; cursor blinks but nothing is typed
4. Observe the tab selection flickering rapidly

Expected behavior

Input field should remain responsive regardless of how many sessions/tabs are open.

Workaround found

Restarting the terminal/extension host processes seems to resolve it temporarily.