Are you using multiple monitors (laptop lcd + external for example)? At least for me the password dialog appears sometimes in "wrong" (detached) display. Also I sometimes have witnessed dialog not being shown on single display setup, but when I enter my password to this non-visible dialog I can still unlock the desktop.
Are you using multiple monitors (laptop lcd + external for example)? At least for me the password dialog appears sometimes in "wrong" (detached) display. Also I sometimes have witnessed dialog not being shown on single display setup, but when I enter my password to this non-visible dialog I can still unlock the desktop.