Double Commander vs Thunar

You can use same tool in all desktop OS environments.

If the developer loses interest there is at least the possibility that someone else will pick up the torch.

Lots of options allow you to configure DC the way it suits you best: Tools, Fonts, Colors, Hotkeys, Mouse, Fileviews, Plugins, Layout, Toolbars, Tabs, Icons etc.

Save shortcuts to folders. Organize them in a treeview with submenus. Define a name and sorting for each entry.

so you can use documentation from Total Commander for writing plugins. WCX (packer), WDX (content), WFX (file system), WLX (lister).

For instance, the 'Settings | Layout' pane is quasi-identical to TCs.

Although it is lightweight and simple to use, it can do very sophisticated tasks, like copying files from directories which have a certain extension or file size or have a certain text pattern in them. Also, it's very customizable and stable.

It's all a matter of perspective. I'm not for an argument about IDE's, frameworks etc, but to me that's a big plus. I think it should be a tie, it's either a pro or a con or should that be neither a pro nor a con. It just depends on context.

Unlike Nautilus, which requires the whole GNOME desktop, thunar just depends on some XFCE utilities & GTK.

While in a Thunar window, typing either a "~" or a "/" will automatically start typing into the "address-bar" and pressing enter goes straight to the typed directory.

In a thunar window, any non-directory typing will search in the current directory for the filename that you type (non-recursive, unlike Nautilus)

Select multiple files in the current folder using a wildcard pattern.

Use Custom Actions to add right-click options to do things like Open as Root, Open Git GUI, etc. You can filter the file types and filename patterns that the actions will show up for.

To add an "Open as Root" action, go to Edit, Configure custom actions. Assign a name and a description. Set Command as "gksudo xdg-open %f" (you'll need to install gksudo since pkexec won't work). Pick an icon (I prefer "changes-allow"). Under Appearance Conditions, select Directories, Text Files, and Other Files.

Supports the M4 and M5 mouse buttons for forward/back, similarly to most browsers.

With also predefined functions as insert (date, numbering,...), search/replace, etc ...

Browse files in two directories with a dual pane view.

But nothing more.

While in a Thunar window, typing a filename automatically selects the first matching file in the current folder.

Thunar can use the editable accelerator feature of XFCE.

Run xfce4-appearance-settings in terminal, go to settings tab, check "enable editable accelerator". Now open any command in Thunar menu, hover to a command, i.e. your custom "places" or your custom command, then press any combination to assign a shortcut to it.
be careful though, cause it will also remove the shortcut from other command.

Use tabs to open fewer windows. New tabs automatically start in the same location. Tabs can be detached.