Trace on the score page when dragging glissando
It's a little bit difficult to explain. The screencast may help to understand the problem:
As you can see, when we drag a glissando from the palette, it lets a trace in the score page. The bug occurs only when dragging from left to right, not right to left. When the cursor moves outside the score page, the traces disappear completely.
Config: MuseScore 7ab8acd on Xubuntu 14.10.