Actually there was not issue with pro and you thought you had issue with file manager add-on with missing file,
You said you are seeing following error:
jquery.jgrowl.map:1 GET https://webstuffdepot.com/wp-content/plugins/wpdm-filemanager/assets/jGrowl/jquery.jgrowl.map 404 (Not Found)
bootstrap.css.map:1 GET https://webstuffdepot.com/wp-content/plugins/wpdm-filemanager/assets/bootstrap3.1.1/css/bootstrap.css.map 404 (Not Found)
But as our support team mentioned in last reply, there was also no missing file, here is the copy of reply
In fact there is no such file with .map extension, neither they are enqueued from the add-on, the file names enqueued from the add-ons are jquery.jgrowl.min.css , jquery.jgrowl.min.js and bootstrap.css, so what you seeing certainly causing by other active plugin or theme and not an issue with file manager add-on, try deactivating other plugin to find which one is causing the issue.”
So there was actually nothing to fix from our side and what you explained in your review is not true.
