Volta hook length doesn't get saved in file

When the length of the last hook of a volta is changed and then the file is saved, the change is not saved in the file. After reloading the file the last hook has the default length. Images below to clarify:

Before saving:

After saving and reloading:

I'm using version 0.9.6 rev 3101M.
The MuseScore file is attached below, but for me it happens with all files.