www-plugins/mplayerplug-in-3.55-r1 breaks gettext catalogs installation. It worked with previous in-portage version. This has been caused by insensitive ebuild changes. Readding code from previous version should fix it.
Created attachment 196348 [details, diff] www-plugins/mplayerplug-in-3.55-r1 patch installing catalogs This patch reintroduces catalog installation. Getting currently USEd languages is a little odd (I thought some automagic with LINGUAS variable has been added into PMS, but I did not found any documentation). If you don't like it, just omit the code in src_unpack() and it will install all translations regardless USE flags.