HI! We have our back-end set to Dutch. But in the mAvik Thumbnails plugin we see a lot of untranslated language strings. We see those untransled string also when we set the back-end language to English.
We installed the latest version of the plugin today. This was after an upgrade of the site form Joomla 2.5 to 3.4.
You should remove language files of plugin from administration/language
They look as administration/language/xx-XX/xx-XX.plg_content_mavikthumbnails.ini and administration/language/xx-XX/xx-XX.plg_content_mavikthumbnails.sys.ini
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