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System: Linux php-prod-1.spaceapp.ru 5.15.0-160-generic #170-Ubuntu SMP Wed Oct 1 10:06:56 UTC 2025 x86_64
User: xnsbb3110 (1041)
PHP: 8.1.33
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$ pwd: /home/shaping-sar.ru/public_html/wp-content/plugins/js_composer2/locale/
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File: /home/shaping-sar.ru/public_html/wp-content/plugins/js_composer2/locale/readme.txt
Official info about translation: http://codex.wordpress.org/Translating_WordPress

In two words: open default.po file and save new copy as js_composer-es_ES.po for Spanish.
And then use translating program to translate it to Spanish language.
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