It means that there are some extra tags in your files giving those results in the column browser. To fix it, you will probably need to use Tag Inspector. For each file, select it and open the Tag Editor by pressing Shift+Enter together. Then open the Tag Inspector by clicking the button near the top of the Tag Editor window. Finally, scroll down the listed values on the right hand side until you see the strange characters. Select the value and click the third button down in the right hand column (looks like -). This will delete the value. Click save in the Tag Inspector and Tag Editor windows.
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