How to extract a list of all 18 character entries after specific phrase in string using RegExr?

Question

I managed to extract a list of the text within square brackets within an emoji list I have here:

https://regexr.com/3sqk1

But now I need to extract the equivalent decimalSurrogateHtml pairs for each emoji (I know a few of them have 2 pairs but would be fine just to extract the first pair to the right of the following text)

"decimalSurrogateHtml":"��",

I'm looking to extract just the 18 characters to the right of "decimalSurrogateHtml":

Does anyone know the expression I should enter to retrieve a list of these?

Thanks