I tried as you wrote but I failed to translate these two strings. in WPForms...
After I scanned the plugins I still couldn't find them in the Translate manager.
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When we speaking about problems with strings I can't find, I have another one.
I was translating the footer yesterday and I managed to translate all but one word (Industrije), I even found it in "Translate texts in admin screens" and translated it but it still throws out the word in the original language.
You translated the wrong string and the correct one was set to the wrong source language. I changed the source language to Bosnian then translated the text and it works now.