How do I remove all the trailing dashes in the mode line of terminal Emacs?

Question

In terminal Emacs:

Look at the mode line. Notice that there are lots of dashes (hyphen-minuses, to be precise) (-----) at the end of the mode line (after "(Lisp Interaction)"). How do I remove these dashes?

These dashes only seem to appear in terminal Emacs but not in GUI Emacs.

(I am using GNU Emacs 25.2 on Ubuntu 18.04 bionic beaver).

Answer 1

It appears that the dashes are caused by the variable mode-line-end-spaces, which is the last item in mode-line-format by default. The default value of mode-line-end-spaces is (:eval (unless (display-graphic-p) "-%-")), which explains why the dashes only appear in terminal Emacs but not in GUI Emacs.

This seems to remove the dashes, but I'm not sure if there are any adverse side effects:

(setq-default mode-line-end-spaces nil)

This also seems to remove the dashes:

(setq-default mode-line-format (remove 'mode-line-end-spaces mode-line-format))

Result:

Perhaps someone more experienced with Emacs Lisp could comment on the validity of the methods above.