Translucent Toolbar Background Issue in iOS Safari Private Browsing Mode After Enabling Dark Mode and Single Tab Navigation from Safari Settings

hi. I've come across a UI-related bug. It's not a critical issue, but I'm curious whether it's actually a bug or an intended result.

1. Enable "Dark Mode" on your device.
2. Set Safari to "single tab" mode in the settings.
3. Open the iOS browser.
4. Switch to "Private Browsing" mode.
5. When swiping up, the background of the top toolbar (including the status bar) becomes translucent, revealing the content behind it.

• When I turn on the 'Reduce Transparency' setting, the issue does not occur, and the background content remains hidden as expected.

iPhone12 mini / iOS 17.0.1

thx!