Make MCP server's WebSocket bridge idempotent across windows - #2
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Opening multiple editor windows each spawns its own mcp_server.py, and every instance raced to bind port 8788 for the Figma plugin, crashing all but the first. Now a losing instance polls a shared-state file the port holder writes on each message instead of crashing, and keeps retrying the bind so it takes over automatically if that process exits.
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Summary
mcp_server.py, and every instance tried to bind port 8788 for the Figma plugin — only the first succeeded, the rest crashed instead of serving their window's MCP tools._run_websocket_bridgenow loops: on a bind failure it doesn't crash, it reads a shared-state file (written by whichever instance currently holds the port on every plugin message) and retries the bind every 5s, so it self-promotes to leader automatically if that process exits.ui.html's Settings > MCP Connect panel byte-identical to.mcp-server/mcp_server.pyper the file's own sync note.Test plan
node --test tests/code-regression.test.jspasses