Never heard about that issue, either.
What I would try:
- uninstall Inkscape, make a backup of the /home/<username>/.config/inkscape directory and delete it.
- reinstall Inkscape
If it doesn't work correctly then:
- uninstall, delete inkscape user config directory
- reinstall Inkscape, current version, from the other source (not the ppa, in your case, I assume, but you can find out which version is used by typing:
apt-cache policy inkscape)
Please report back if any of that helped.