Aaron Edwards

Tired of your custom plugin and theme translation files getting wiped out every time you use the WordPress auto-updater? Install and activate this plugin and 
WordPress will look for missing translation files in the WP_LANG_DIR where you keep your WordPress translation files.
<h4>UPDATE</h4>
In WordPress 3.8 and greater this plugin’s functionality is included in core. You can put translation files in: 
* Plugins: /wp-content/languages/plugins/textdomain-locale.mo 
* Themes: /wp-content/languages/themes/textdomain-locale.mo
A free plugin by Aaron Edwards of <a href="http://uglyrobot.com/" rel="nofollow ugc">UglyRobot Web Development</a>.

Translation Preserver

A simple plugin that helps preserve your custom plugin translations through auto-updates by allowing you to put them in your WP languages folder.

Per Søderlind

On posts where comments are closed, the plugin will remove the text ‘Comments are closed.’ The plugin supports any languages/text domain, and will remove the text from themes and plugins.
Prerequisite: Since the plugin is <a href="https://codex.wordpress.org/Plugin_API/Filter_Reference/gettext" rel="nofollow ugc">filtering gettext</a>, your theme/plugin must be <a href="http://wp.smashingmagazine.com/2011/12/29/internationalizing-localizing-wordpress-theme/" rel="nofollow ugc">localized</a>.
View the plugin source code at the <a href="http://soderlind.no/archives/2012/01/11/wordpress-plugin-remove-comments-are-closed/" rel="nofollow ugc">plugin home page</a>

Remove "Comments are closed"

Remove the "Comments are closed" text from posts.

Translation Preserver vs Remove "Comments are closed"