Free, dual pane file manager with tabs, comes as installer or portable version, heavily customizable
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Pro Portable version available
Pro Separate tree for each panel
Pro Heavily customizable
Besides many customizable on-board options and features, one can also write his/her own scripts and even full plug-ins.
Pro Both 32 bit and 64 bit versions available
Pro Written in C++
The program launches fast.
Pro File coloring based on filters
Including optional background coloring.
Limitation of this pro: text and background color cannot be taken from 2 different filters and thus combined but on the positive side: it provides coloring profiles, which can be switched (supposedly easily).
Pro Full of features
A hundred different options: multi-rename, convert line break of files (CR, LF, CRLF), double panel, folder tree, tabbed interface, colourized tabs, etc.
Pro Support for FTP, Registry, and OneDrive
Pro Powerful scripting system
You can easily write powerful scripts even without knowledge of programming.