Very minor thing, but somewhat confusing. Suppose we are in this situation:
This is a line, with some words on it, which| continues on the next line. So the cursor is at the end of the line. Suppose I now type a space. The display does not change in any way. But the space is there, and if I type a letter it will suddenly appear. It's a bit confusing, since sometimes I'm not sure if I typed the space, then I type it again, and LyX scolds me. Riki