The beta and preview channels got some extra fixes yesterday including the following:
General
Fixed a crash related to http transfers
Desktop Mode
Fixed -silent command-line option not working
Fixed windows not grouping together in the taskbar
Fixed pinning a steam window to the taskbar resulting in a shortcut that could not launch steam
Fixed association of steam windows with the steam.desktop application entry
Steam Input
Virtual Menus now work in the desktop overlay
Added binding listener dialog that lets you bind inputs by hitting a mouse button, keyboard key, or gamepad button
LED Color/Brightness Action reinstated as a bindable action. Find the Action settings inside the GamePad tab when selecting an action binding (available on controllers with LEDs only)
Fixed the controller configurator not fully closing when backing out via the gamepad in the Desktop overlay
Fixed the controller configurator opening layout previews in a new window instead of directly in the configurator
Fixed cases where alt-tabbing between the stand-alone instance of the desktop configurator and a game would not update the in-game layout
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