Hard to navigate past code block by keyboard

### Is this a hackmd.io issue?

- [x] Yes, the bug happens on https://hackmd.io
- [ ] No. If it's a self-hosted CodiMD instance, please fire up the issue in the repo of CodiMD: https://github.com/hackmdio/codimd

### What's the problem

#### Current behaviour

> Screenshot (optional)


Provide steps to reproduce:

1. Create a code block with a specified syntax (see screenshot)
2. Move cursor to the end of a line
3. Hit up key to go to previous lines
4. Get stuck on popup on syntax line

https://hackmd.io/@ajorg/stuck-up-at-syntax-line

#### Expected behaviour

I should be able to continue navigating my document with only the keyboard.

#### Environment

I use HackMD on:

**Desktop**
- OS: chromeOS
- Browser: chrome
- Browser Version: 126

#### Additional context

If the popup is really necessary, maybe when I press up when the top line of the popup is selected it should go up. I really dislike the popup though. This is a text editing window and doesn't need UIs to be popping up in front of me without my using a mouse.