The "extras" command:

Usage: fossil extras ?OPTIONS? ?PATH1 ...?

Print a list of all files in the source tree that are not part of the
only files in the given directories will be listed.

Files and subdirectories whose names begin with "." are normally
ignored but can be included by adding the --dotfiles option.

Files whose names match any of the glob patterns in the "ignore-glob"
setting are ignored. This setting can be overridden by the --ignore
option, whose CSG argument is a comma-separated list of glob patterns.

Pathnames are displayed according to the "relative-paths" setting,
unless overridden by the --abs-paths or --rel-paths options.

Options:
--abs-paths      Display absolute pathnames.
--case-sensitive <BOOL> override case-sensitive setting
--dotfiles       include files beginning with a dot (".")
--header         Identify the repository if there are extras
--ignore <CSG>   ignore files matching patterns from the argument
--rel-paths      Display pathnames relative to the current working
directory.