When running debug on a pattern you might notice that some string temporary variables are truncated.
Where if you right-click on the value of the variable and click "Copy", paste that into a text editor, that the value has "..." in the middle when it should not.
[start of the string]...[end of the string]
There is limitation on how many characters are stored on the temp variables while debugging (and only debugging, does not happen in runtime).
The field itself is not truncated.
You can use the "Parse Variable" operation step to "Retrieve" the whole variable. Then you can pick out the parts you need from the output.