Hi

What happens when you select the light theme?

Is your operating system set to a dark or light theme?

Nothing happens - it doesn't respond to switch from dark to light or vice versa. I had an update today and it fixed the issue in the non-private version but Private Browsing still is purple - and dark bookmark listings

Aha, private windows. Could you try this:

(1) Toggle a setting

(A) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button accepting the risk.

More info on about:config: Configuration Editor for Firefox. The moderators would like us to remind you that changes made through this back door aren't fully supported and aren't guaranteed to continue working in the future.

(B) In the search box in the page, type or paste browser.theme.dark-private-windows and pause while the list is filtered

(C) Double-click the preference to switch the value from true to false

(2) Open a new private window to check the sidebar

In my test, the open window wasn't affected by the settings change, but a new one was.