I have the same problem. It is frustrating. Are there any solutions or fixes in the works for this issue. My understanding is that it is a common issue. I am working from an iMac. I am also using DuckDuckGo to searches. Need to have safe and secure browsing. Open to any and all suggestions! Let me know if it is an operator error.

My first thought is that even though the new window opened, the focus might be on a different window.

On Windows, I would suggest pressing Alt+Spacebar, which calls up a universal window control menu from the upper left of the currently focused window. Does it come up on the private window?

Not sure whether there is such a thing on Mac.

My second thought is that this reminds me of someone who said that the address bar occasionally just stops noticing new typing -- the text appears in the bar but the drop-down no longer adapts to the expanded text. Are you either of you noticing that?

The new window for private browsing does not have the focus. Alt+Spacebar does not bring up the menu until I click somewhere on the tab. Opening a new tab has no problem and returning to Firefox from another program has no problem. Also this only happens when I right click the desktop icon to launch the window. This does not happen when I open a new private window from the menu in Firefox.

Hmm, I see that on Windows 10 right-clicking the Taskbar icon and clicking either Open new window or New private window. Not sure why it isn't getting the focus.