I've recently installed QGIS 3.4. Earlier today, my vertex tool showed a virtual node at the center of line segments (as it should with the new node tool). This is no longer showing while editing the same shapefile (although I can add nodes at the end of the polyline). It also doesn't highlight in red, as in the user documentation. Are there any settings I should check or troubleshooting ideas before I reinstall again? I did mess with the snapping options, but it doesn't seem to matter if I remove snapping.