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17th December 2025

Tool Codex Timeline Viewer — View Mozilla Codex rollout timeline events from `.jsonl` files with an interactive interface that supports filtering, searching, and detailed event inspection. Load files via drag-and-drop, paste, or URL fetch, then explore events organized chronologically with customizable timezone display and comprehensive event details including formatted content, tool calls, and reasoning blocks.

This is a beat by Simon Willison, posted on 17th December 2025.

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