I've got it!!! Thank you a lot Alex!

On my site I was missing that small image from this code... there was ? mark instead of image...for all reactions. And my code looked a bit different (took the code from una13b4 and pasted it to current rc2) :

a:5:{s:5:"emoji";s:4:"?";s:4:"icon";s:0:"";s:5:"color";s:20:"sys-colored col-gray";s:6:"weight";s:1:"1";s:7:"default";s:9:"thumbs-up";}

instead of

a:5:{s:5:"emoji";s:4:"👍";s:4:"icon";s:0:"";s:5:"color";s:20:"sys-colored col-gray";s:6:"weight";s:1:"1";s:7:"default";s:9:"thumbs-up";}

Now it is working as supposed to. Thank You Alex for your directions!!!!