macOS: chat input becomes barely usable after the first response #17001

Environment

• OS: macOS (Darwin 25.2.0, arm64)
• OpenCode version: 1.2.24
• Install method: bun
• Terminals tested: iTerm2, Kitty

Problem

After the first assistant response, the chat input box becomes very unreliable.

Typing starts to lag badly or misses key presses. To enter a single letter, I often need to press the key 2-5 times.

This makes the TUI effectively unusable after 1-2 messages.

Reproduction

1. Open a terminal on macOS
2. Start opencode
3. Open any existing session or create a new one
4. Type a prompt into the chat box and send it
5. Wait for the assistant response to complete
6. Start typing the next message

Expected behavior

The input box should continue accepting keystrokes normally after each response.

Actual behavior

After the first response, input handling becomes very poor:

• keystrokes are often dropped
• typing feels laggy or unresponsive
• a single character may require 2-5 key presses

Notes

• Reproduces consistently
• Happens on macOS only
• Reproduces in both iTerm2 and Kitty, so it does not seem terminal-specific
• OpenCode, Bun, and terminals are all updated to latest versions
• Workaround is to fully restart the TUI and reopen the same session

Possibly related

• Unstable TUI #3935
• The terminal UI display is abnormal #1146
• shift+enter keybinding not working #1505
• Opencode stuck in "generating" #2512
• Opencode hangs after loading Context7 Remote MCP server #1244