# Entry preview setup The entry preview is created using the same mechanism as used by the [Custom export filter](/v4/import-export/export/customexports.md) facility. When previewed, an entry is processed using one of the two alternative layouts (you can switch between the two layouts by pressing F9) to produce HTML code which is displayed by the preview panel. To modify the appearance and contents of the preview you need to edit the preview layouts using the syntax described in the help file on [Custom export filters](/v4/import-export/export/customexports.md). --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.jabref.org/v4/setup/preview.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.