This not true is my system. I’ve just plugged a phone configured as mass storage via USB to copy some files (that I presume that were also cached), and the Safely Remove’ icon under the taskbar refused to remove it, saying that the device was in use by a program. After killing ExpressCache.exe via taskmanager, it could be instantly removed without any error.
I’ve faced the same behaviour too with a regular flash pen drive under 1.3.0.
