Actually, I can't found any invisible characters when I copy your data and paste them into Power BI Desktop. In your scenario, you can add a custom column as below. let Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45W8nB19AnxUPD0c/MP8nUM8fT3Uwhxdf...
Invisible characters and blank characters are kind of space. But it happens in the Unicode character. We use it when we have to send invisible letter.