htmx 4.0.0 has been released!
Summary
htmx 4.0.0 release announces major upgrades, including a migration from XMLHttpRequest to fetch(), explicit attribute inheritance, standardized event names, and a new history model that re-fetches on back navigation. It introduces Morph Swaps, the <hx-partial> feature, and a suite of extensions (hx-preload, hx-download, hx-history-cache, hx-live, hx-sse, hx-ws, hx-multipart). The post also covers upgrading guidance, installation options, and notes that htmx 2.x remains supported alongside the new 4.x line.