- * C. If the blob is *not* located in any type of WIM resource, then we don't
- * know any additional information.
+ * C. If the blob is *not* located in any type of WIM resource, for example
+ * if it's in a external file that was scanned by wimlib_add_image(), then
+ * we usually won't know any more information. The sha1_hash might be
+ * known, and prior to wimlib v1.13.6 it always was; however, in wimlib
+ * v1.13.6 and later, the sha1_hash might not be known in this case.