To enhance your JDownloader 2 experience, navigate to Settings > Advanced Settings and adjust the parameters to create an ad-free environment and enable a sleek dark mode that looks better to me than the default options.

KeyValue
GraphicalUserInterfaceSettings: Bannerfalse
GraphicalUserInterfaceSettings: Donate Button StateHidden (Automode)
GraphicalUserInterfaceSettings: Look And Feel ThemeBLACK_EYE
GraphicalUserInterfaceSettings: Premium Alert ETA Columnfalse
GraphicalUserInterfaceSettings: Premium Alert Speed Columnfalse
GraphicalUserInterfaceSettings: Premium Alert Task Columnfalse
GraphicalUserInterfaceSettings: Special Deal Oboom Dialog Visible On Startupfalse
GraphicalUserInterfaceSettings: Special Dealsfalse
LAFSettings: Color For Config Header Text Color#ffffffff
LAFSettings: Color For Config Panel Description Text#ffffffff
LAFSettings: Color For Panel Background#ff222222
LAFSettings: Color For Panel Header Background#ff222222
LAFSettings: Color For Panel Header Foreground#ffffffff
LAFSettings: Color For Speed Meter Average Text#ffffffff
LAFSettings: Color For Speed Meter Text#ffffffff
LAFSettings: Color For Table Account Error Row Foreground#ffffffff
LAFSettings: Color For Table Account Temp Error Row Foreground#ffffffff
LAFSettings: Color For Table Alternate Row Background#ff222222
LAFSettings: Color For Table Alternate Row Foreground#ffffffff
LAFSettings: Color For Table Mouse Over Row Background#ff666666
LAFSettings: Color For Table Mouse Over Row Foreground#ffffffff
LAFSettings: Color For Table Package Row Background#ff333333
LAFSettings: Color For Table Package Row Foreground#ffffffff
LAFSettings: Color For Table Selected Rows Background#ff666666
LAFSettings: Color For Table Selected Rows Foreground#ffffffff
LAFSettings: Color For Tooltip Foreground#ffffffff
LAFSettings: Config Disabled Text Color#ff666666
LAFSettings: Config Enabled Text Color#ffffffff