I translate manually program interfaces. Of course, I must update translations if there are new software versions.
But often the files are very long and cannot be translated in one go. Therefore I would have a feature that highlightens the identical untranslated strings only and by that I can jump from identical to identical string. The different strings should be white and the identical strings should be highlightened by any other color, for instance red. This way I can compare a file in the original language (most often English) with another file in the translation language and see right off, which strings are still untranslated.