The description, played by Cheryl Fergison, had recorded Dot Cotton a tape before she was wrecked by Ben Mitchell in 2012.
In her final day in the launderette, Dot discovered the lost tape and smiled as she listened ago to it.
“Hello Mrs. Branning, its Heather here,” the voice said.
“I was going to get you a present-day, but me and Shir got drunk on woo woos, and I spent all my cash.”
“This is DJ Hev wishing you a Happy Christmas,” she added, before Linda Henry’s character Shirley interceded in as well.
Cheryl had seemingly returned to the soap specifically to record the new colloquy, and was duly listed as the end credits rolled.
The cameo-of-sorts was received warmly online, with one viewer theme: “Lovely touch! Still miss Hev!!!”
“how lovely was Dots message from Heather on band @bbceastenders fitting tribute to Dot. Loved tonight’s ep #byedot,” said another.
A third created: “In tears tonight watching @bbceastenders miss you Heather trot xxx.”
Yet another posted: “@cherylfergison1 Heather’s no mix tape left me a bit teary eyed, #eastenders #heather #goodolddays.”
EastEnders pursues today at 9:30pm with its Christmas Day special on BBC One.