• Added configurable asset transformers, which can be managed from Settings → Assets → Asset Transformers and assigned to asset volumes by handle.
• Added CraftCms\Cms\Asset\AssetTransformers and CraftCms\Cms\Asset\AssetTransformDrivers.
• Added CraftCms\Cms\Config\GeneralConfig::$defaultAssetTransformer.
• Replaced Craft’s system status with Laravel maintenance mode, including an admin-only Maintenance Mode control in General Settings.
• Removed CraftCms\Cms\Config\GeneralConfig::$isSystemLive, app()->isLive(), and the core craft:on and craft:off commands. Deprecated compatibility remains available through craftcms/yii2-adapter.
• Moved the generateTransformsBeforePageLoad setting to Craft Asset Transformer profiles.
• Removed per-call immediate generation arguments from the core Asset Transform APIs and GraphQL transform arguments.
• Removed the core image transformer registry, contracts, fallback transformer, and execution methods from CraftCms\Cms\Image\ImageTransforms. Legacy equivalents remain available through craftcms/yii2-adapter.
• Improved environment variable and alias settings fields to show suggestions after typing $ or @, automatically bracing embedded environment variables.
• Improved new password fields to provide the configured password rules to supported password managers. (#19516)
• Element edit screens now autosave at the pace of the change — a keystroke waits, a discrete change saves almost immediately.
• Submitting an element edit screen now cancels any in-flight autosave, and a failed autosave reports its HTTP status.
• Element edit screens now indicate which fields a draft has unapplied changes to.
• Fixed a bug where the Control Panel loaded two copies of Lit, which could break rendering within legacy HTML controls.
• Fixed a bug where field layout changes weren’t saved on entry type settings screens.
• Fixed a bug where Typecast would throw when trying to set properties that didn’t exist. (#19492)
• Fixed a bug where POST requests to legacy action URLs weren’t getting routed properly. (#19478)
• Fixed a JavaScript error that occurred when creating a new Dashboard widget. (#19479)
• Fixed a bug where users without a local password could not start an elevated session using OAuth. (#19512)
• Fixed a bug where Yii log targets configured via config/craft/app.php did not receive messages logged with Craft::info() and related methods. (#19517)
• Moved filesystem URL settings to CraftCms\Cms\Filesystem\Filesystems\Local, with legacy filesystem compatibility remaining available through craftcms/yii2-adapter. (#19525)