To be clear, you can’t disable the markdown feature, per se. You can edit how it appears so it doesn’t look like code anymore.
The exact CSS will depend on what the rest of your CSS is, however.
The “easiest” way is to open up your theme’s .css file, find the selector the theme uses to style paragraph text, and then add the code selector to that set of style instructions (I don’t know the selector offhand). Depending on how the CSS file is structured, however, this may not be straightforward.
Otherwise, you can custom-style this type of code. It looks like cm-hmd-indented-code is the selector, so you’re looking to add a snippet for something like:
.cm-hmd-indented-code {
color: var(--text-normal);
font: var(--text);
}
However, there’s a lot of assumptions baked into that snippet. It might work, it might not. You might want to look at some of the “getting started with CSS” stuff on the forum to be able to troubleshoot it!