Note: This update was re-released on June 8th with the following additional fixes:General
Fixed bug preventing upload of game download statistics
Fixed occasional crash on Steam startup
Fixed bug causing some values in the server browser to show up as negative
Fixed bug adding library folders on external drives in some cases

macOS
Fixed bug preventing game launches on macOS 10.12
Fixed intermittent crash in Dota 2 during game startup

Steam Input
Fixed bug with chorded inputs bound to the ABXY buttons
Fixed bug with square deadzones on joysticks where full deflection would result in mirrored output

A new Steam client has been released and will be automatically downloaded.General
Added new game properties page to manage subscribed workshop items
Fixed potential game install state corruption during Steam client shutdown
Fixed Workshop item download loop in some cases
Fixed erroneous creation of empty popup windows when a Steam Store link is opened through middle click from a Community page or vice versa

Chat
Added an option to upload your last in-game screenshot through the paperclip menu in a chat window
Fixed popup windows being created with wrong position and size on Windows when running on multiple monitors with different DPI settings

macOS
Fixed background flickering in some games when Steam Overlay is visible

Steam Input
Fixed some cases where modes bound in Action Set Layers would not work or improperly show up as empty
Fixed issue with repeated events not firing properly for Trackpads bound as a Button Pad
Added more legacy trigger settings to trigger modes in Steam Input API configurations
Fixed an issue with binding joystick axis outputs to buttons

SteamVR
Fixed regression in prompts to install SteamVR and appropriate drivers when installing new hardware
Fixed issue that caused Steam to trigger Game Theater for certain overlay applications.,,Read More