macOS version misidentified in CCleaner for Mac Posted November 19, 2020 A tiny bug, but a very odd one. In the latest CCleaner for macOS (v. 1.18.30), it identifies the OS version as 10.16. But I'm running Big Sur, version 11.0.1. How could it get this wrong? Not a big deal, and no response expected, but maybe someone at Piriform will notice it.