LO 6.3 on Ubuntu19.10 or LM19.2
Open a new text-document and enter 
. The auto-correction will adjust the entered text into a coloured emoticon .
Now save the document as a pdf-document. The emoticon isn’t ported into the pdf-document. If you install the symbola-font and modifies the character-font into symbola, a monkey in black-and-white will be shown. This emoticon will be properly saved into the pdf-file (as will be the font).
If you examine the properties of the first saved pdf- file, you’ll notice that the font NotoColorEmoji is saved into the pdf-file. The font installed on the computer = 2.017;GOOG;noto-emoji:20180810:f1da3bc656f9.
Do we have to install another font? Or why is this font not rendered into the pdf-file?