LightDM issue (dialog box disappears)

Folks, I have started having this problem:
When I boot in at the start into AL with LDM, there is no problem.
But after logging in (to dwm, though I don’t think it would be diff for any other WM) when I log out with Alt-Shift-Q, it logs out, takes me back to a fully functional LDM screen with a dialog box to input my login info. So far no problem.
But in about 3 seconds, the dialog box disappears on its own. Now, I know it is there somewhere, because if I type in my password, it does log me back into dwm, but I can’t figure out why it is disappearing. Have spent about an hour on this looking into possible settings in xprofile or xinitrc. It is not either, b/c even if I remove these 2 files, exactly same behavior happens.

All help appreciated.

–My thoughts are for Samuel Paty, I feel so sorry, I feel helpless, and I wish so much I could have been there to help and protect you. A simple school teacher just like me.