I did. It turns out that installing graphicsmagick does the trick (pun intended) for Noto Color Emoji. However, the issue persists for SVG fonts and the same message appears, despite of having cleaned the cache (I've used mtxrun --script cache --erase). Using the code Pablo sent, with EmojiOne Color instead of Twemoji Mozilla, I get the following error messages:

LMTX (error):

function call [998]: ...mtx/tex/texmf-context/tex/context/base/mkiv/mlib-svg.lua:1471: bad argument #1 to 'gsub' (string expected, got nil)

MKIV (outlined emojis, flag emojis not working):

fonts > svg conversion > executing runner 'otfsvg': inkscape --export-area-drawing --shell > temp-otf-svg-shape.log

fonts > svg conversion > processing 1829 svg containers

xml > core > load error: invalid xml file - parsed text

(the line below repeated dozens of times)

fonts > svg conversion > processing can be going on for a while

fonts > svg conversion > processing 1829 pdf results

fonts > svg conversion > there are no converted shapes, fix your setup

fonts > svg conversion > svg conversion time 4.246 seconds

In any event, LMTX prints only black and white emojis.

On 5/20/2020 9:31 PM, Pablo Rodriguez wrote:
> On 5/20/20 12:26 PM, Jairo A. del Rio wrote:
>> [...]
>> Only Twemoji Mozilla and Segoe UI Emoji worked for me, so, what am I
>> doing wrong?
>
> Hi Jairo,
>
> using latest ConTeXt with the following sample, I get these results:
>
> \definefontfamily[emoj][rm][Twemoji Mozilla][features={color}]
> \setupbodyfont[emoj]
> \starttext
> 🤦🇬🇧
> \stoptext
>
> MkIV (2020.01.30 14:13) displays colored icons.
>
> LMTX (2020.05.18 16:50) displays only black and white icons.
>
> I think this might be a bug in LMTX.
>
> Could you confirm the issue?
what if you wipe the cache