20 March 2019 inquiry

In November I got a response to How do I fix a frozen black screen on Lubuntu startup? from karel to consult https://askubuntu.com/tags/nomodeset/info

I initially opened grub from etc/default and changed:




It wouldn't let me save the changes though! It opened it in leafpad, but I didn't have the permissions!

Karel's followup comment suggested I run it as root to get permission via this command in the terminal:

sudo nano /etc/default/grub

I am sure most would recommend getting familiarity with the terminal. I did figure it out, because I changed it (keyboard arrows only to navigate, no mouseclicks!) and upon exiting it prompted me to save, and I did, and then ran `sudo update grub afterward as both the wiki and Karel said to.

I was searching more on the topic and found How to edit GRUB file at /etc/default/ where in 2013 someone recommended using something called gksu to edit as root. Is this still around? I couldn't find it in Synaptic Package Manager when I searched it.

I'm looking for alternative means of root editing (perhaps via Leadpad, which is how grub opened by default when I double clicked it) which are a little easier on the eyes and mind than editing in the terminal is.

For now I am going to reboot and see if this fixed things. Would anyone know about the issue raised at How do you add lines to /etc/default/grub so they're reflected in /boot/grub/grub.cfg? and if there is some special considerations for /boot/grub/grub.cfg? in selecting what graphic drivers to run at startup?

I get this message when I do "Advanced Options" and then "Recovery Mode" then "Resume Boot"

some graphics drivers require a full graphical boot and so will fail when resuming from recovery

I assume doing this 'nomodeset' is similar, except rather than the drivers failing, they don't try to initiate at all, so I could do a regular startup. I will be trying this now and will update with results.

  • The text editor Kate will ask you for a sudo password when trying to write a file you don't have write permissions on. It will then elevate its permissions to write the file, so no need to run it as root in the first place (which sudo nano, gksu leafpad etc. do). gksu and gksudo are not available in the repositories anymore and will probably never come back. – danzel Mar 20 '19 at 10:09

gksu is deprecated and no longer available.

Many people recommend command line tools for administration tasks, for example

sudo nano filename

But if you really need a program with a graphical user interface, there are solutions:

  • If the program is prepared for it


    or select the program via the menu or dash and you will be prompted for password

  • pkexec GUI-program

  • sudo -H GUI-program

Never use plain sudo GUI-program because it can damage your userID's configuration files.

If you are using Wayland (instead of the old Xorg), there is more complication, described at the following link,

Why don't gksu/gksudo or launching a graphical application with sudo work with Wayland?

| improve this answer | |

Not the answer you're looking for? Browse other questions tagged or ask your own question.