Hello, Thx very much for the solution : . If you are experiencing video lagging try resetting your SMC: Power off MAC and leave the plug attached Hold down Shift + Ctrl + Option and Power On button for 10 Secs. Release buttons and then power on mac. This should remedy most issues with the new update Happy Crimbo. It fix it for me ! MacBook Pro (Retina, 13-inch, Early 2015) 2,7 GHz Intel Core i5 Intel Iris Graphics 6100 1536 Mo

You said : "Going to battery under system preferences and unchecking Automatic Graphics Switching fixed this for me.". Where that ??? There is nothing in battery preference with Big Sur !! Who can help please ? :-(

Hi, same for me, how to fix it ? MacBook Pro (Retina, 13-inch, Early 2015) 2,7 GHz Intel Core i5 Intel Iris Graphics 6100 1536 Mo