One of the first things junior developers learn the hard way when they are starting out is the importance of using CLIPPED with CHAR variables. If you forget CLIPPED when concatenating CHAR you will see some spaces in the middle of your concatenated string.
With the prevalence of STRING variables, developers can fall into the habit of not using CLIPPED, particularly when passing arguments to functions. ui.ComboBox.addItem calls and methods involving filenames are the common places where the CLIPPED is forgotten.
Read more at
https://4js.com/ask-reuben/ig-244/