--- Comment #6 from Heiko Tietze <[hidden email]> ---
(In reply to Vladimir from comment #5)
> There is "Edit filter settings" option in the file dialog, which is grayed
> out for HTML. Isn't it the obvious place for such options?
Not in my dialog (KDE, Save As). It depends on the OS/DE what you get and
LibreOffice just adds the few checkboxes below the Filter dropdown (to my
knowledge there are no other opportunities to tweak the dialog; and doing it
yourself is doomed, see the inbuilt file dialog).