"Eric Sunshine via GitGitGadget" [off-list ref] writes:

+	$checked =~ s/(\?![^?]+\?!)/$c->{bold}$c->{red}$1$c->{reset}/mg;

It may be just me, but coloring the whole "?!LOOP?!" in red feels a
bit strange.  I would have expected more like

	if ($c->{color_in_use}) {
		$checked =~ s/\?!([^?]+)\?!/$c->{bold}$c->{red}$1$c->{reset}/mg;
	}

IOW, switching between "?!LOOP?!" and "<BOLD><RED>LOOP<RESET>".

But it may be just me.

+# Restore TERM if test framework set it to "dumb" so 'tput' will work; do this
+# outside of get_colors() since under 'ithreads' all threads use %ENV of main
+# thread and ignore %ENV changes in subthreads.
+$ENV{TERM} = $ENV{USER_TERM} if $ENV{USER_TERM};

Sounds quite sensible.