How do I make the markup menu persist at the top of screenshot?

I understand your frustration.

One thing you could do is set the screenshots to open in Preview:

Command-Shift-5, click Options, and choose "Preview" under "Save to".

This would still not immediately open the Markup Toolbar automatically, but in Preview it can be opened with Command-Shift-A, which is much quicker than using the mouse or trackpad to click.

You don't. You can send Apple feedback if you like.

Feedback - macOS - Apple

There are some features present in older versions of macOS like Monterey with did not make it through to newer version of macOS.

To be blunt about this - Apple Designed the Operating System macOS 14 Sonoma

As learned colleague mentioned and to use different terms.

There is zero we " mere mortals " can do about this outside of registering our displeasure in a polite manner to Apple

cleanapp wrote:

How do I make the markup menu persist at the top of screenshot the way it used to before?

https://discussions.apple.com/content/attachment/ade75438-385e-481d-b98e-6d567f2b8f80

https://discussions.apple.com/content/attachment/ec7f157a-2dce-4a03-b4f2-635aeffb8238

What the user appears to be presenting is a Quick Look in Sonoma macOS 14.4.1 ?

View and edit files with Quick Look on Mac

First image is a Quick Look of a png screen shot

Click the A with circle in Top Menu of Quick Look appears normal and in top Menu Bar

Second image is same Quick Look but clicking the A with circle expands the Tool Bar In Top Menu Bar

Revealing more editing options

No one here can answer "why" questions. We're all end users like yourself.

Sorry, I may have missed the " top of screenshot " aspect of your question

You're welcome.

Maybe not for us non-typists. 😎