Changelog

All notable changes to Plasmate, tracked by version and date.

v0.4.0 2026-03-23

Chrome-delegated screenshots, completed SPA hydration, and full CDP stub coverage for Puppeteer compatibility.

• feat Chrome-delegated screenshots for pixel-perfect rendering via Page.captureScreenshot.
• feat Completed SPA hydration ops: insertBefore, replaceChild, classList, cloneNode.
• feat Timer queue drain for setTimeout and requestAnimationFrame.
• feat Wired page.click() and page.type() via DOM bridge.
• feat Implemented page.waitForSelector() for final DOM state.
• fix Fixed all remaining CDP stubs, including setDeviceMetricsOverride, addScriptToEvaluateOnNewDocument, getLayoutMetrics, and getProperties for improved Puppeteer compatibility.

v0.3.0 2026-03-22

SPA rendering, interaction APIs, plugin system, and multi-session support. ~25K lines Rust, 200+ tests passing.

• feat Network request interception - block, modify, or mock responses.
• feat TLS configuration - cipher suite and fingerprint tuning.
• feat Wasm plugin system - optional feature flag, wasmtime runtime.
• feat SPA rendering bridge - bidirectional V8/rcdom DOM sync, SOM recompiled after JS.
• feat Timer queue drain for React/Vue deferred rendering.
• feat page.click(), page.type(), page.waitForSelector() via DOM bridge.
• feat Deep SPA hydration - insertBefore, replaceChild, cloneNode, classList.
• feat Multi-page session manager - 50 concurrent sessions per instance.
• feat Auth profiles with encrypted cookie storage.
• feat Screenshots protocol surface (SOM fallback until renderer lands).

Stats

• Binary: 45.8 MB default / 54 MB with plugins
• Memory: 28 MB RSS per process
• Tests: 200+ passing
• Codebase: ~25K lines Rust

v0.2.0 2026-03-21

V8 integration, CDP server, SDK expansion, and coverage tooling.

• feat V8 JavaScript integration with full DOM shim.
• feat CDP server for Puppeteer/Playwright compatibility.
• feat MCP server mode (stdio JSON-RPC).
• feat SOM Specification v1.0 with JSON Schema and conformance test suite.
• feat Node.js SDK with full TypeScript types.
• feat Python SDK with Pydantic models.
• feat Go SDK with structs, client, and query helpers.
• feat Throughput CI benchmark expansion to 100 URLs across 13 categories.
• feat CDP cookie jar (getCookies, setCookies, deleteCookies, clearBrowserCookies).
• docs Browser Use and LangChain integration pages.
• docs Interactive coverage scorecards (nightly HTML, weekly JS).

v0.1.1 2026-03-20

Major JS runtime improvements. Coverage jumps from 71% to 82%.

• feat Functional MutationObserver for SPA framework support (React, Vue, Next.js). Observer callbacks now fire on DOM mutations, enabling client-side rendering in the headless engine.
• feat URL/URLSearchParams polyfills with try-catch constructor probing. Detects partial V8 built-ins and only overrides when necessary.
• feat JS coverage scorecard tracking 100 real-world sites with per-site element counts, JS failure rates, and error details.
• fix Browser-realistic HTTP headers to avoid anti-bot blocking (zero speed/memory cost).
• fix Pre/post JS SOM comparison keeps whichever SOM has more elements, preventing JS from degrading content.
• fix Skip type="module" external scripts (prevents SyntaxError: Cannot use import statement outside a module).
• fix var self = globalThis for SPA frameworks that reference self.
• perf Configurable JS safety budgets: --max-external-scripts, --max-external-script-kb, --external-script-timeout-ms.

Coverage Results

• HTML scorecard: 80/100 Full (80%)
• JS scorecard: 79/98 Full (80.6%)
• New Full sites: amazon.com, ebay.com (via MutationObserver)
• Remaining thin: 14 sites needing deeper DOM mutation support
• Failed: 4 (anti-bot: etsy, tripadvisor, wsj; non-HTML: httpbin)

v0.1.0 2026-03-01

Initial public release. The browser engine for agents.

• feat Semantic Object Model (SOM) compiler: HTML to structured, token-efficient representation.
• feat Agent Web Protocol (AWP): 7-method protocol for agent-native browsing (navigate, snapshot, click, type, scroll, select, extract).
• feat V8 JavaScript runtime with DOM shim for JS-rendered pages.
• feat CDP compatibility layer for Puppeteer/Playwright drop-in usage.
• feat MCP server mode (plasmate mcp) with stateful tools: open_page, evaluate, click, close_page.
• feat Cookie-based auth profiles with AES-256-GCM encryption at rest.
• feat Chrome extension bridge for importing auth sessions from a real browser.
• feat Docker image on GHCR (multi-arch).
• feat Node.js and Python SDKs.
• perf 4-5ms per page (50x faster than Chrome, 5x faster than Lightpanda).
• perf ~30MB memory for 100 concurrent pages.
• perf 10.4x token compression vs raw DOM.

Architecture

• Language: Rust (16,740 lines at launch, 171 tests)
• Binary: 43 MB single file, no dependencies
• License: Apache 2.0