Usually, a double dash separates options from filenames, but xdg-open does not care:
❯ xdg-open -headlinesAfter.epub
xdg-open: unexpected option '-headlinesAfter.epub'
Try 'xdg-open --help' for more information.
❯ xdg-open -- -headlinesAfter.epub
xdg-open: unexpected option '--'
Try 'xdg-open --help' for more information.
Is there any other way?