See also bug #725493 ("Moving cursor in dash text entry field causes cursor artifacts"):
The Dash cursor height changes depending on whether the box is empty (displaying the faded hint "Search") or whether the user has typed in it. Ideally the cursor height should be constant. This is possibly that the text height is not being setup until text needs to be drawn, and so it is falling back to the system default.
See also bug #725493 ("Moving cursor in dash text entry field causes cursor artifacts"):
The Dash cursor height changes depending on whether the box is empty (displaying the faded hint "Search") or whether the user has typed in it. Ideally the cursor height should be constant. This is possibly that the text height is not being setup until text needs to be drawn, and so it is falling back to the system default.