Question
Why does my JS file have <% when it was not in the source file
Answer
This can cause an issue with minified files. If the user uses the Developer Template to add minified code that contains <$, the <$ will convert to <% and break the minified code, causing a "<%1>" to appear on the page.
Minified files should be uploaded directly, not use the Developer Template. To resolve the issue, branch the asset that is using the Developer Template, and uncheck it in the content properties, then push through worfklow.