Do you have a desire for this particular solution, or are you looking for any solution to your underlying problem?

Is your underlying problem that you want to be able to easily edit while reading through the preview?

Would a side by side view that scrolls the raw text in step with the preview be a suitable solution on desktop? Would a similar approach on mobile work if it were above and below rather than side by side?

I ask because personally I would expect to prefer this to having to jump back and forth between raw text and preview.

trichoplax‭ Both; which is one reason I'm in support for better layouting and functionality overall, on the editor page, but that's a separate concern. The preview exists so you can read through the post as it will be displayed, which is what I'm using it for. I often find typos when reading it, and I also use it to better navigate through my text. The input text box is unpleasant to read through, because of a number of factors: monospace without syntax highlighting (like in source code), inline links, etc. The formatting is part of the source.

Would a side by side view that scrolls the raw text in step with the preview be a suitable solution on desktop? Would a similar approach on mobile work if it were above and below rather than side by side?

Maybe, but I can imagine that being rather annoying. Every now and then, I read through a different part of the preview than where I am writing in the source.

Would a similar approach on mobile work if it were above and below rather than side by side?

Don't think so.

Every now and then, I read through a different part of the preview than where I am writing in the source.

I see what you mean - sometimes I'm writing something based on wording from earlier in the same post so I would need the scrolling of source and preview to be in different parts of the post.

I wonder if it could work with a checkbox to lock or unlock the scrolling. Then we could have both scrolling in step when it's convenient, but also untick the checkbox when we want to scroll them to different positions. I guess this is a discussion for a different post though.

Yeah, that seems like more work when all I want to do is for a double-click to take me where I am in the preview, to the source.