Developer Finds Safari MCP Server Bug That Silently Mints Invalid Tab Tokens

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A developer discovered a critical bug in their Safari MCP server where browser tab ownership tokens became invalid after a daemon restart. The flaw stemmed from a cached browser-session epoch in the extension's background worker that was never refreshed from storage, causing newly minted tokens to carry a stale identifier. When the worker eventually cold-started, it discarded all stored records tied to the outdated epoch, instantly invalidating every token created during the restart window. Affected tabs became permanently stranded — commands were refused and the tokens could not be rotated or recovered from the client side. The bug went undetected because six separate safety checks all passed silently, with only the final rehydration path actually comparing the epoch against storage.

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Gubernator Brings Autoscaling to Docker Without Kubernetes Overhead

A new open-source container orchestrator called Gubernator (gbnt) has been developed to provide horizontal autoscaling for Docker-based workloads without requiring Kubernetes. The tool lets teams use standard docker-compose.yml files while gaining automatic scaling based on real-time CPU and NVIDIA GPU utilization metrics. Every 10–15 seconds, Gubernator's autoscaler evaluates container performance via Prometheus and cAdvisor, then calculates desired replica counts using a threshold-based formula with cooldown guards to prevent erratic scaling. Autoscaling policies are declared directly through gbnt.autoscaling.* labels inside existing Compose files, eliminating the need for proprietary manifests. The platform positions itself as a middle ground between the simplicity of Docker Swarm and the governance features of enterprise-grade orchestration systems.

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ProgrammingDEV Community ·

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CSS Flexbox vs Grid: A Beginner's Guide to Choosing the Right Layout Tool

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