Look there: https://cdn.dhtmlx.com/suite/pro/edge/suite.js
There is o.i18n=e.dhx&&e.dhx.i18n?e.dhx.i18:{} code. I think it shold be o.i18n=e.dhx&&e.dhx.i18n?e.dhx.i18n:{} instead, because e.dhx.18 probably is undefined.
Thank you for your note. We’ll recheck the sources and fix the problem.