Sure. Basically, I want :extend to apply to a line with a folded region even though the newline at the end itself does not have the :extend property. So I want the extend property to somehow propagate across a line to the newline at the end, even if it does not have the :extend property. This would allow for :extend to work as expected when we have a a folded region that extends across multiple lines but the end of the folded region does not have the :extend property. I don’t think this would cause unexpected behavior since :extend on non-newline characters is currently a no-op. Eli Zaretskii writes: >> From: StrawberryTea >> Cc: juri@linkov.net, kevin.legouguec@gmail.com, 65896@debbugs.gnu.org, >> yantar92@posteo.net >> Date: Sat, 30 Sep 2023 17:55:27 -0500 >> >> Basically, when the text is folded, it uses the face of the first visible >> newline after the fold to determine the background. >> >> The elisp approach is to maintain overlays at the end of each folded region and >> it becomes complicated with nested headings. I was thinking that instead, we >> could have the extend property (or an extra option on :extend) be used within >> the line to colorize the background of the newline at the end. > > Sorry, I still don’t understand what you mean by the last sentence. > (All the rest is understood, but it describes the current situation, > which I understand well enough to not need any explanations.)