i've been using BleachBit to clean up free space on my laptops HDD, and also on my encrypted portable HDD. and i've got same problem on both devices. Bleachbit was running very long, i left it overnight, but in the morning i decided to kill process. after that i deleted all files and directories created by bleachbit (as root). but still got some space mysteriuosly "lost" in ubuntu when i open disk properties, this space is marked "dark grey" color on the pie diagram. blue stands for used, white stands for free space. and wtf is this dark grey? and how can i regain it? any thoughts? see attached image. and thanks for help in advance.