I've had this issue as well. Judging from the Manjaro forums, it happens to more users than it doesn't. I have seen accounts of it happening on LXQT, KDE, but hadn't seen confirmation on i3 or XFCE, yet. (Now we know...)
In my experience, I often get the black screen as you describe with NOTHING on the screen, absolutely no terminal-like cursor. Once, out of frustration while rebooting to try and get to the login screen, I put it down without turning it off. When I came back to it several minutes later, I tapped the trackpad, the mouse moved, and there was the login! I haven't sat down and timed it yet, but after 10-15m, my black screen will be the full desktop. It has done this whether I left the lid open or closed. Now, if I don't get the login the first or second try, I just put it down and come back to it after a break.
I'm really hoping that once the hardware support is solidified in mainline, we'll see this behavior stop.
In my experience, I often get the black screen as you describe with NOTHING on the screen, absolutely no terminal-like cursor. Once, out of frustration while rebooting to try and get to the login screen, I put it down without turning it off. When I came back to it several minutes later, I tapped the trackpad, the mouse moved, and there was the login! I haven't sat down and timed it yet, but after 10-15m, my black screen will be the full desktop. It has done this whether I left the lid open or closed. Now, if I don't get the login the first or second try, I just put it down and come back to it after a break.
I'm really hoping that once the hardware support is solidified in mainline, we'll see this behavior stop.