> For the complete documentation index, see [llms.txt](https://docs.jabref.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.jabref.org/v4/setup/preview.md).

# 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).