There is currently a setting in Obsidian that lets you specify what mode new notes open in. However, it would be nice if there was a similar setting that specifies what mode existing notes open in. Currently opening an existing note opens it in whatever mode your previous note was in.
I like to refer back to notes when I’m writing, or would want to quickly lookup a note for reference while I’m working. I find it very annoying to have to hit ctrl+e every time I want to quickly take a look at another note, and then hit ctrl + e again when I go back to editing the previous note, especially since this happens all the time.