Calibre -

: You can make these fields visible in the main book details pane by navigating to Preferences > Look & Feel > Book details and checking your new column.

: While standard fields are easy to bulk edit, long text fields (like Comments) can be trickier. You may need to use Regex (Regular Expressions) within the bulk metadata edit dialog to find and replace specific formatting or repeated text across many books. Calibre

Give it a (e.g., mynotes ) and a Column heading (e.g., "Notes"). Restart Calibre to see the change. Tips for Working with Long Text : You can make these fields visible in

: Calibre supports searching the entire content of your books, not just the metadata. Click the "FT" button on the left of the search bar to enable or use the full-text search interface. Give it a (e

: If you need to extract all text from a book into a single long file, it is often easier to convert the book to .txt or .rtf format first rather than trying to "select all" in the viewer.