Midnight Commander

User-friendly text console file manager and visual shell

Midnight Commander is a visual shell much like a file manager, only with many more features. It is a text mode application. Midnight Commander's best features are its ability to FTP, view tar and zip files, and to poke into RPMs for specific files.

Source:
https://codeberg.org/cyclotouriste/mc-for-sailfish

FAQ

# The subshell gives a segfault

Sailfish uses busybox ash by default. To avoid problems with Midnight Commander, using bash might be better.
You can switch to bash with this command as root:
  # pkcon remove busybox-symlinks-bash