When I click "Apply" in settings of DrJava, it says:
Could not save changes to your ".drjava" file in your home directory. java.io.IOException: Permission denied
Permissions are:
drwxr-xr-x 30 pypaut pypaut 4096 avril 14 12:24 /home/pypaut
-rw-r--r-- 1 root root 1259 janv. 1 2017 /home/pypaut/.drjava
Something created the .drjava directory with root ownership (or later chown'd it that way). You'll need to reset that to be your user:
sudo chown pypaut:pypaut ~/.drjava
If you do not have root-level authority to do this, you could rename the directory:
mv ~/.drjava ~/.aside-drjava
mkdir ~/.drjava
ls -ld $HOME $HOME/.drjavadrwxr-xr-x 30 pypaut pypaut 4096 avril 14 12:24 /home/pypaut-rw-r--r-- 1 root root 1259 janv. 1 2017 /home/pypaut/.drjava