Sumatra 3.1.2 64 , Windows 10
When i copy an emojis from a pdf with sumatra, and paste on a document, it shows a slightly different emoji.
In the pdf shows 
, but coping from sumatra to any editor gives me 
It’s kind of weird, it shows correctly on sumatra, but after coping it changes.
This problem is fixed on newer versions of Sumatra, but these versions can’t open external files, like mp3 and videos, it gives the “error loading” “path_to_file” message
The only version that can be “fixed” is 3.3 (soon)
The problems with extracting imbedded objects such as mp3 were due to many changes to the MuPDF core code (some related to file security) those issues are known but will not be fixed in time for 3.3 (so keep a copy of 3.1.2 for alternate extraction methods.
It is possible to set an “external viewers” command in 3.2 or 3.3 to open a file you are reading in a copy of SumatraPDF 3.1.2. as & when needed.
For the problem of not opening mp3/video files, please open an issue at Issues · sumatrapdfreader/sumatrapdf · GitHub and attach a sample document.