"Close" option on dialog boxes
In many dialog boxes, such as for uploading files or images, or adding tags, the dialog has options of "Close" and "Save" (or similar, I don't have an example in front of me). It's not clear that clicking "Close" would cause the dialog to be ignored, e.g., the file would not be uploaded. In most other systems this would be labeled "Cancel" and users understand that whatever information has been given in the dialog would be lost.
I suggest we say "Cancel" rather than "Close" in these cases to clarify that information would be lost.
This is a small matter but would improve the user experience.