Bug: Cursor not visible in editor when using dark mode

[Valdas3]

Summary

When you click on an editor to edit code you cannot see where the cursor is since it has a similar color to the background.

Where did you spot the bug?

https://developer.mozilla.org/en-US/docs/Web/HTML/Element/details

What is the problem?

Can't see the cursor.

What did you expect to happen?

To see the cursor

Steps to reproduce the issue

1. Open https://developer.mozilla.org/en-US/docs/Web/HTML/Element/details Firefox
2. Click on the editable text in the editor for "HTML Demo: <details>"

Environment

Device

• Desktop

Browser

• Firefox: (98.0b3)

Operating system

• Windows

Screenshots