Show or hide initial first line heading

As we dump in a lot of existing Markdown content, most of it has an initial # or ## heading. It would be good to show/hide this via a global or then vault specific preference setting as the file name is already most likely reflecting the contents.

Is custom styles in obsidian.css an option for you?

That would also work, best if across all custom and default styles. Seems I switch CSS once a week for the same vault.

/* This should hide first H1 tag in notes */
.CodeMirror-code > div:first-child > .HyperMD-header-1 {
  display: none;
} 

/* This do the same for markdown-preview */
.markdown-preview-view > div:first-child h1:first-child {
  display: none;
}

EDIT: Update the code for preview mode.