Electron 39.0.0 brings upgrades to Chromium 142.0.7444.52, Node 22.20.0, and V8 14.2. The ASAR integrity feature, which validates packaged apps against build-time hashes to prevent tampering, graduates from experimental to stable. New features include hardware acceleration detection, HDR color space support for offscreen rendering, granular accessibility management, and dynamic ESM imports in preloads. Breaking changes include deprecation of the --host-rules command line switch in favor of --host-resolver-rules, always-resizable window.open popups per WHATWG spec, and restructured shared texture OSR paint event data. Electron 36.x.y reaches end-of-support.