My 02c....
(As posted in the Malwarebytes support forum)
Malwarebytes 4.1.2.73 and Windows 10 2004
Previously, all three of my computers running 2004 have had the performance problems with earlier versions of Malwarebytes including the beta version that was suggested as a workaround/fix.
I eventually turned off Malwarebytes until a permanent fix to this performance problem had been sorted out.
Today I updated Malwarebytes to the latest version on one of my computers, hoping it has fixed the extreme performance issues it causes to Windows 10 2004.
Unfortunately it hasn't been fixed, because as soon as I started Malwarebytes v4.1.2.73, the performance issue started again, with programmes and apps not starting, Windows itself becoming unresponsive, and my computer locking up. These problems went away as soon as I managed to turned off Malwarebytes.
Another issue I have found as well with all previous versions of Malwarebytes is that it slows down my daily differential backups on all my computers. I use Macrium Reflect to back up all my computers daily (differential file and folder backup) and Weekly (full backup of Files and Folders, and a disc image backup of the OS drive)
With Malwarebytes running, the daily differential backups take over and hour to complete, with Malwarebytes turned off, they only take about 20 minutes.
For my weekly full File and Folder backups with Malwarebytes turned on, they take about three hours to complete, with Malwarebytes turned off, they only take about an hour to complete.
I am, at the moment only using Malwarebytes as an 'on demand' security app.
I have a premium subscription for Malwarebytes which is due to expire in November, and with these performance issues being caused by Malwarebytes, I will most likely not be renewing my subscription, and will just revert back to using Malwarebytes free as an on demand backup security programme.