What is this weird watermark style message icon/textbox?

[Android Central Question]

Hello, since updating to Oreo this morning, I've noticed a strange watermark style orange message icon with an ellipsis in and a text box on the bottom 1/4 of my screen. It's very faint but also one of those "can't unsee" issues and I'm working during what it could be! Will try to upload a screenshot on white screen.

TIA

 

[dov1978]

Burn in? Screen retention?

 

[belodion]

Oo-er. It’s not the dreaded screen-burn, is it?
What phone?

Edit: Posted same moment as above.