Steam Update Today
They mention Improved startup times for users with a large number of games
November 5, 2015 - Steam Client Update Released
Improved startup times for users with a large number of games
Added a "Update News" option to the view menu so you can go back to past offers and view their details
Changed controller Steam/Xbox button behavior to fix a collision with the hold-down-for-4-seconds method of turning off the controller:
Old behavior: Hold down 3 seconds to launch Big Picture (or single press if you were in desktop Steam).
New behavior: Pressing once will change focus to Steam if it doesn't have focus. If it has focus, pressing once will launch Big Picture.
Fixed the friends dialog sometimes dismissing if your network connection dropped and reconnected
Fixed play button for non-Steam games showing "Preload" in some cases
Fixed a possible crash when running a badly-formed steam:// URL
Improved hover behavior when using the mouse to navigate
Significantly improved performance in the Library area for users with a large number of games
Updated status bar look at the top of the main menu
Reorganized the Settings section and fixed several issues with individual pages
Web browser shows hand cursor when hovering over web link
Added support for multiple game library folders
Added support for picking your default install library for Games
Improved performance when rendering large amounts of text
Fixed Steam overlay flickering when using multiple NVIDIA GPUs in SLI configuration
Fixed bad on-screen positioning of Big Picture mode after running games that change display settings
Fixed unexpected switch out of Big Picture mode when displaying content validation messages
Fixed getting stuck in the Library screenshot viewer if you used the guide button
Fixed web pages being partially transparent when moving
Fixed rare crash when navigating through large lists
Fixed crash when using daisy wheel in the Web browser
Fixed mouse wheel not working when hovering the right grid in the Library
Fixed "New For You" items not activating when selected
Fixed in-game crash when using the Daisy Wheel keyboard
Fixed buttons mis-firing on the Steam Controller right after leaving a game
Fixed view CD key button in the overlay being styled incorrectly
Fixed getting stuck in the overlay if you backed out of certain panels before they fully loaded
Fixed focus going to the wrong place if you deleted the last game from the Disk Management page under settings
Added a new trackpad mode, Mouse Joystick. This is an alternate way of emulating mouse-style controls for games that disable mouse input when using a gamepad. For best results, we recommend increasing the gamepad camera sensitivity/speed in the game settings.
Added a new trackpad mode, Touch Menu. This mode is useful to bind many infrequently-used hotkeys to a single trackpad. The Big Picture in-game overlay has to be enabled for this feature to work.
Added support for custom controller configurations for Desktop mode
Added option to turn off steam controller when leaving Big Picture mode.
Additional work to prevent noise and drift for the gyro when in a steady state. Calibration will refine when left idle for five seconds if current configuration uses Gyro. If drift is severe, leave idle for 15 seconds for repeated refinements. Note that "always on" is not required for auto-calibration, it happens regardless of button activation.
Made trigger soft and full pull mode-shift and gyro-enable capable buttons
Added the ability to mode shift triggers
Mouse Rotation horizon line visualization is now shown/hidden when adjusted
Added Trigger Mouse Dampening. Squeezing the trigger can now engage a dampening factor to the mouse mode.
Added Joystick Camera option to Gyro.
Added Invert Horizontal and Invert Vertical to mouse/joystick modes.
Added options to configure the suggestion modes of the dualtouch keyboard
Added Legacy configuration option for games with In Game Actions, allowing users to access advanced settings.
Mouse Rotation now visualized as a horizon line when changing the slider.
Gyro Enable Button is now visible in the gyro preferences.
Added support for keyboard/mouse emulation on Mac
Fixed a client crash when running a game with an invalid official controller configuration
Fixed some "gyro enable button" options not applying properly
Fixed bugs preventing controllers from showing up under settings when using a Steam Link
Fixed properly showing binding descriptions for games that have an official configuration
Fixed an issue with emulated analog stick sometimes moving in the wrong direction when fully deflected
Fixed Trigger modes getting stuck on Hip Fire Aggressive
Fixed Rotation visualization for Mouse Joystick
Fixed Mode Shifts not showing up properly on main controller overview.
Fixed Mode Shifts not being disabled by setting the shift button to none.
Fixed loss of input in Portal 2 after losing focus or activating the overlay
Reduced CPU usage of the streaming client software
Enabled hardware encoding by default, please report issues on the bug forum
Added workarounds for some multi-monitor issues with NVFBC capture mode
Updated AMD hardware encoding SDK for improved Win8+ performance
Improved performance and fixed garbled picture with AMD hardware encoding
Improved performance of some video capture methods for windowed games
Disabled some incompatible capture methods if AMD Crossfire is detected
Improved support for rotated (portrait-mode) monitors
Changed desktop mode to capture one monitor at a time and follow the mouse across monitors
Fixed incorrect display cropping on Linux clients when hardware accelerated decoding is enabled
Fixed a potential cause of black screens when hosting games on a computer with multiple GPUs
Fixed low resolution due to Windows display-scaling settings in NVFBC capture mode
Fixed bugs with streaming multiple-monitor desktops on Windows 8 and higher
Fixed incorrect mouse coordinates in some situations with Windows 8.1 and Windows 10
Fixed a crash if the user exits Steam while a streaming session is still active
Fixed some causes of audio stutter when streaming at high bitrate
Fixed always-black video on some multi-GPU, multi-monitor systems
Fixed issues with Toki Tori 2 and several other games which rely on VSync for animation timing
Fixed crashes on systems with certain AMD video drivers
Fixed low capture resolution when running games on a high-DPI monitor
Fixed mouse cursor position when text scaling is enabled on the host computer
Fixed mouse clipping issue with fullscreen games
SteamOS + Linux
Added support for Captured Portal (i.e Hotel Wifi) network configurations
Improved compatibility with XCB games
Fixed being unable to type shifted characters from the virtual keyboard
Mac OS X
Fixed focus issues when displaying 2 modal dialogs at the same time
Fixed slow shutdown when you had a Steam Controller connected
Added a warning and link to troubleshooting steps when Steam detects that Windows Compatibility Mode is interfering with internal functionality
Improved compatibility of the Steam overlay with other third-party overlay software