Sidebar is not available in private windows

Feedback Nightly Builds
1

I enabled sidebar at brave:://flags. I can use it in ordinary windows but in private windows it disappears.

OS: Xubuntu 20.04
Brave version: Version 1.35.7 Chromium: 96.0.4664.55 (Official Build) nightly (64-bit)

2

try reinstalling brave