We're in the process of updating the documentation for Zotero 5.0. Some documentation may be outdated in the meantime. Thanks for your understanding.
Default Output Format – Sets the style to be used when copying a reference to the clipboard using the Quick Copy shortcut keys, or drag-and-drop.
Copy as HTML – Changes the Quick Copy output from plain text to HTML.
Site-Specific Settings – Overrides the default Quick Copy style when a particular web site domain is open in the Firefox browser. This makes the use of different styles in different contexts quick and easy.
See Zotero and Wikipedia for more information.
Display character encoding option on export - By default, Zotero auto-detects the proper character encoding when you export bibliographic data. However, when this option is checked, Zotero will prompt you to specify the encoding standard before exporting.
Import Character Encoding By default, Zotero auto-detects the proper character encoding when you import bibliographic data. If this doesn't work correctly, you can specify the correct character encoding here.