Commande "chmod -R 777

sudo mkdir /tmp/mount
sudo mount /dev/sdb1 /tmp/mount
#Theoriquement le proprio est déja root mais
sudo chown root:root /tmp/mount/usr/bin/sudo
sudo chmod 4755 /tmp/mount/usr/bin/sudo
sudo sync
sudo umount /tmp/mount
reboot

Tools > Customize > Toolbars

That should be the location of the option to change the icons. By default, I don't think it comes with more than just the default options.

If you search for packages starting with "libreoffice-style-" you can install some different themes. 
 

sudo

sudo

sudo

sudo

(mando@aldur) (~) $ ls -l  $(which sudo) 
-rwsr-xr-x 1 root root 145040 Jun  8 19:57 /usr/bin/sudo

/usr/bin/sudo

sudo -s

su -

/

/dev/sda2

sudo fdisk -l

Disk /dev/sdb: 59.6 GiB, 64023257088 bytes, 125045424 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x000c20ab

Device     Boot    Start       End  Sectors  Size Id Type
/dev/sdb1           2048   7813119  7811072  3.7G 82 Linux swap / Solaris
/dev/sdb2        7813120  66406399 58593280   28G 83 Linux
/dev/sdb3       66406400 125044735 58638336   28G 83 Linux

/

/mnt/linux

mkdir -p /mnt/linux
mount /dev/sda2 /mnt/linux
chroot /mnt/linux

sudo

chmod 755 /usr/bin/sudo
chown root:root /usr/bin/sudo 
chmod  u+s /usr/bin/sudo

exit
cd /
umount /mnt/linux
reboot

sudo

gksudo

sudo -s

su -

sudo

sudo

sudo sh lenom.sh |tee repair_perm.log

#!/bin/sh
laSource=/usr;

find $laSource -name "*" -exec sh -c '\
utilisateur=exileur; \
laDest=/tmp/mount; \
badUtilisateur=ubuntu; \
fileUser=$(stat -c "%U" "$0"); \
fileGroup=$(stat -c "%G" "$0"); \
filePerm=$(stat -c "%a" "$0"); \
if [ $fileUser=$badUtilisateur ]; then fileUser=$utilisateur; fi; \
if [ $fileGroup=$badUtilisateur ]; then fileGroup=$utilisateur; fi; \
if [ -f "$laDest$0" ]||[ -d "$laDest$0/" ]; then \
chown -v "$fileUser:$fileGroup" "$laDest$0" && chmod -v $filePerm "$laDest$0"; \
fi;
' {} \;