Recs.
Updated
Files (also known by its former name, Nautilus) is the official file manager for Gnome. It has an emphasis on being intuitive and simple, and follows the Gnome Human Interface Guidelines.
Specs
Pros
Pro Widely supported
The program is distributed as a single source archive, which can be configured, compiled and installed on almost any Linux flavor. There are no binary files for a specific Linux distribution, but you can install it directly from the default software channels of your operating system.
Pro Easy to use and familiar user interface for Ubuntu users
The user interface of Files is very familiar to Ubuntu users, most probably because Canonical still uses Nautilus (an old version of it) as the default file manager for its world’s most popular free operating system, Ubuntu Linux.
It split into two parts, a sidebar and the main file viewer. While you already know what the latter can do for you, the sidebar offers quick access to Places, Devices and Network locations, as well as any other bookmarks that you can add whenever you want.
Pro Allows you to access remote or local locations
On recent versions of GNOME, you can click the Files entry in the panel to access a specific location (remote or local), connect to a certain server (FTP, SFTP, SAMBA, etc.), access your bookmarks, open a new window, as well as to change its default functionality.
Cons
Con It has lost so much functionality
As already stated, this is not well configurable anymore. One can not even start in dual pane mode for cut/copy and paste. Just a ridiculous transgression. It was great just 1-2 years ago, but over-simplification in this case is detrimental to functionality.
Con Awful date modified column.
It should list by full year month day, no matter whether it was today, last month or years ago. Displays wrong time modified for photos I took and downloaded today (not exif time taken and not anything that makes sense). Not customizable in any way one would expect.
Con Slow at moving picture folders
A move, even to the same disk, can take a minute for a folder containing a hundred images.
Con Creating sub-folders within full folders is not possible anymore.
In order to create a new folder within another folder that is full to the bottom of the page, we must create a folder in an open area somewhere else, then move the sub-folder into that full folder. Even worse, we need to use the "Move to..." option, with so many extra clicks, instead of just being able to copy and paste as before.
Con "+ Other Locations" is a stupid change
"+ Other Locations" in the left pane now forces us to click twice or more in order to access additional drives, even the local "Computer." Having all of the drives listed on the left side was quick and easy, and the drive "Properties" were available just by right clicking once, although drive "Properties" is no longer available when clicking on "+ Other Locations," then right clicking on the drives.
I still use Debian 8 for the older Nautilus, even though the developers already damaged that older version as well. However, Nautilus is completely useless to me now in Debian 10 so I am seeking for a new graphical desktop to replace Gnome and Nautilus...I am fed up with the developers.
Con Has too many bugs
There are too many bugs at the current state for this file browser to be usable.