A minor issue in my opinion as I have only seen this
with one windows application, namely "putty".
Putty by default has a black background and a white
However when the cursor moves into text area of putty
terminal it disappears because it is black on black.
By way of comparison, in a Windows RDP client session
to same server, running putty, the cursor is white
against the black background of the putty terminal text
window and therfore can be seen.