Speaking of formatting, this forum formats 3 dashes (which I assume you typed) as an em-dash.
If you want to show the actual input you are using, surround it with triple backticks. ```
For example:
Test
---
And then we can see what you are actually inputting.
Otherwise yeah, this is expected Markdown syntax. It turns it to a header. Your other Markdown editors might have just chosen to not implement that syntax. This forum does:
@WhiteNoise@rigmarole Thanks for your patience. Use it or lose it: I never use that header syntax and simply forgot about it, hence I didn’t think to check a syntax guide. This was further reinforced since my other text editor doesn’t implement this.
@rigmarole your assumptions were correct --- so I’ll use this formatting going forward. Formatting related, paragraph breaks never render properly for me in preview mode, regardless of theme, workarounds, etc. And, conversely, I never need to force a line break with syntax to, well, see a line break in preview. I’ll post this, however, properly for help.