okular not building with recommended/optional dependencies

I've noticed that the build log of okular mentions quite a few dependencies that should be included for packaging.

https://build.alpinelinux.org/buildlogs/build-edge-x86_64/community/okular/okular-20.08.2-r0.log

-- The following OPTIONAL packages have not been found:

 * KF5KExiv2
 * EPub
 * QMobipocket (required version >= 2)
 * Discount (required version >= 2)

-- The following RECOMMENDED packages have not been found:

 * LibSpectre (required version >= 0.2), A PostScript rendering library, <https://libspectre.freedesktop.org>
   Support for PS files in okular.
 * CHM, A library for dealing with Microsoft ITSS/CHM format files, <http://www.jedrea.com/chmlib>
   Support CHM files in okular.
 * KF5KHtml, HTML rendering library
   Support CHM files in okular.
 * LibZip, A library for reading, creating, and modifying zip archives, <https://libzip.org/>
   Support CHM files in okular.
 * DjVuLibre (required version >= 3.5.17), A library for dealing with DjVu formatted files, <https://djvulibre.djvuzone.org>
   Support for DjVu files in okular.

Adding the libs libkexiv2-dev libspectre-dev libzip-dev khtml-dev djvulibre-dev ebook-tools-dev kdegraphics-mobipocket-dev discount-dev to makedepends makes only CHM be not found.

As chm support won't be built anyways libzip-dev and khtml-dev can probably be removed again?

This adds 8 new runtime dependencies to okular- but people wanting a lightweight "document viewer" probably won't install okular

(1/10) Installing libdjvulibre (3.5.27-r1)
(2/10) Installing libzip (1.7.3-r1)
(3/10) Installing ebook-tools (0.2.2-r1)
(4/10) Installing discount-libs (2.2.7-r0)
(5/10) Installing kdegraphics-mobipocket (20.08.2-r0)
(6/10) Installing jbig2dec (0.19-r0)
(7/10) Installing ghostscript (9.53.3-r0)
(8/10) Installing libspectre (0.2.9-r0)
(9/10) Replacing okular-common (20.08.2-r0 -> 20.08.2-r0)
(10/10) Replacing okular (20.08.2-r0 -> 20.08.2-r0)

@PureTryOut