diff --git a/Dockerfile b/Dockerfile
index c57f0b806..12c092bef 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -90,6 +90,10 @@ ARG RUNTIME_PACKAGES="\
   tesseract-ocr-fra \
   tesseract-ocr-ita \
   tesseract-ocr-spa \
+  # Suggested for OCRmyPDF
+  pngquant \
+  # Suggested for pikepdf
+  jbig2dec \
   tzdata \
   unpaper \
   # Mime type detection
diff --git a/docs/setup.rst b/docs/setup.rst
index 60fbc212e..3aea55467 100644
--- a/docs/setup.rst
+++ b/docs/setup.rst
@@ -339,7 +339,7 @@ writing. Windows is not and will never be supported.
     *   ``qpdf``
     *   ``liblept5``
     *   ``libxml2``
-    *   ``pngquant``
+    *   ``pngquant`` (suggested for certain PDF image optimizations)
     *   ``zlib1g``
     *   ``tesseract-ocr`` >= 4.0.0 for OCR
     *   ``tesseract-ocr`` language packs (``tesseract-ocr-eng``, ``tesseract-ocr-deu``, etc)