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Add products to your cart and remove them from here Lets buy❓ What does "Missing translation" mean?
#Answer
The plugin tried to show a message that is in neither your translation file nor the one inside the jar. The console names it:
Missing translation for "..."
This almost always means an add-on and the plugin come from different versions. Update both to the latest build and restart.
A key you deleted from your translation file does not cause it. Missing keys are written back with their English default on the next start, and the console prints Missing value for key "..." for each one.