Technology Tales

Adventures & experiences in contemporary technology

A look at Ubuntu GNOME 13.10

12th October 2013

With its final release being near at hand, I decided to have a look at the beta release of Ubuntu GNOME 13.10 to get a sense of what might be coming. A misstep along the way had me inadvertently download and install the 64-bit edition of 13.04 into a VirtualBox virtual machine. The intention to update that to its soon to be released successor was scuppered by instability so I never did get to try out an in situ upgrade to 13.10. What I had in mind was to issue the following command:

gksu update-manager -d

However, I found another one when considering how Ubuntu Server might be upgraded without the GUI application that is the Update Manager. To update to a development version, the following command is what you need:

sudo do-release-upgrade -d

To upgrade to a final release of of a new version of Ubuntu, drop the -d switch from the above to use the following:

sudo do-release-upgrade

There is one further option that isn’t recommended for moving between Ubuntu versions but I use it to get updates such as new kernel subversions that are released:

sudo apt-get dist-upgrade

Rather than trying out the above, I downloaded the latest ISO image for the beta release of Ubuntu GNOME 13.10 and installed onto a VM that instead. Though it is the 32 bit version of the distro that is installed on my main home PC, it has been the 64 bit version that I have been trying. So far, that seems to be behaving itself even if it feels a little sluggish but that could be down to the four year old PC that hosts the virtual machine. For a while, I have been playing with the possibility of an upgrade involving an Intel Core i5 4670K CPU and 16 GB of RAM (useful for running multiple virtual machines at a time) along with any motherboard that supports those so looking at a 64 bit operating system has its uses.

The Linux kernel may be 3.11 but that is not my biggest concern. Neither is the fact that LibreOffice 4.1.2.3 was included and GIMP wasn’t, especially when that could be added easily anyway and it is version 2.8.6 that you get. The move to GNOME Shell 3.8 was what drew me to seeing what was coming because I have been depending on a number extensions. As with WordPress and plugins, GNOME Shell seems to have a tempestuous relationship with some of its extensions and I wanted to see which ones still worked. There also has been a change to the backstage application view in that you either get all installed applications displayed when you browse them or you have to start typing the name of the one you want to select it. Losing the categorical view that has been there until GNOME Shell 3.6 is a step backwards and I hope that version 3.10 has seen some sort of a reinstatement. There is a way to add these categories and the result is not as it once was either; also, it shouldn’t be necessary for anyone to dive into a systems innards to address things like this. With all the constant change, it is little wonder that Cinnamon has become a standalone entity with the release of its version 2.0 and that Debian’s toyed with not going with GNOME for its latest version (7.1 at the time of writing and it picked a good GNOME Shell version in 3.4).

Having had a look at other distribution that already have GNOME Shell 3.8, I knew that a few of my extensions worked with it. The list includes Frippery Bottom Panel, Frippery Move Clock, Places Status Indicator, Removable Drive Menu, Remove Rounded Corners (not really needed with the GNOME Shell theme that I use, Elementary Luna 3.4, but I retain it anyway), Show Desktop Button, User Themes and Ignore_Request_Hide_Titlebar. Because of the changes to the backstage view, I added Frippery Applications Menu in preference to Applications Menu because I have found that to be unstable. Useful new discoveries have included Curtains Up and GNOME Shell Open Terminal while Shell Restart User Menu Entry has made a return and found a use this time around too.

There have been some extensions that were not updated to work with GNOME Shell 3.8 that I have got working. In some cases, it was as simple as updating the metadata.json file for an extension with new version numbers of 3.8 and 3.84 to the list associated with the shell version property. All extensions are to be found in the .local/share/gnome-shell/extensions location in your home directory and each has a dedicated file containing the aforementioned file.

With others, it was a matter of looking in the Looking Glass (execute lg in the box that ALT + F2 brings up on your screen to access this) and seeing what error messages were to be found in there before attempting to correct these in either the extensions’ extension.js files or whatever JavaScript (*.js) file was causing the problem. With either or both of these remedies, I managed to port the four extensions below to GNOME Shell 3.8. In fact, you can download these zip files and install them yourself to see how you get on with them.

Advanced Settings in User Menu

Antisocial Menu

Remove App Menu

Restart Shell Entry

There is a Remove Panel App Menu that works with GNOME Shell 3.8 but I found that it got rid of the Places menu instead of the panel’s App Menu so I tried porting the older extension to see if it behaved itself and it does. With these in place, I have bent Ubuntu GNOME 13.10 to my will ahead of its final release next week and that includes customising Nautilus too. Other than a new version of GNOME Shell, it looks as if it will come with less in the way of drama and a breather like that is no bad thing given that personal computing continues to remain in a state of flux these days.

Turning off seccomp sandbox in vsftpd

21st September 2013

Within the last week, I set up virtual web server using Arch Linux to satisfy my own curiosity since the DIY nature of Arch means that you can build up exactly what you need without having any real constraints put upon you. What didn’t surprise me about this was that it took me more work than the virtual server that I created using Ubuntu Server but I didn’t expect ProFTPD to be missing from the main repositories. The package can be found in the AUR but I didn’t fancy the prospect of dragging more work on myself so I went with vsftpd (Very Secure FTP Daemon) instead. In contrast to ProFTPD, this is available in the standard repositories and there is a guide to its use in the Arch user documentation.

However, while vsftpd worked well just after installation, connections to the virtual FTP soon failed with FileZilla  began issuing uninformative messages. In fact, it was the standard command line FTP client on my Ubuntu machine that was more revealing. It issued the following message that let me to the cause after my engaging the services of Google:

500 OOPS: priv_sock_get_cmd

With version 3.0 of vsftpd, a new feature was introduced and it appears that this has caused problems for a few people. That feature is seccomp sandboxing and it can turned off by adding the following line in /etc/vsftpd.conf:

seccomp_sandbox=NO

That solved my problem and version 3.0.2 of vsftpd should address the issue with seccomp sandboxing anyway. In case, this solution isn’t as robust as it should be because seccomp isn’t supported in the Linux kernel that you are using, turning off the new feature still needs to be an option though.

Customising Nautilus (or Files) in Ubuntu GNOME 13.04

12th September 2013

The changes made to Nautilus, otherwise known as Files, in GNOME Shell 3.6 were contentious and the response of the Linux Mint was to create their own variant called Nemo from the previous version of the application. On the Cinnamon or MATE desktop environments, the then latest version of GNOME’s file manager would have looked like a fish out of water without its application menu in the top panel on the GNOME Shell desktop. It is possible to make a few modifications that help Nautilus to look more at home on those Linux Mint desktops and I have collected them here because they are useful for GNOME Shell users too. Here they are in turn.

Adding Application Menu entries to Location Options Menu

The Location Options menu is what you get on clicking the button with the cog icon on the right-hand side of the application’s location bar. Using Gsettings, it is possible to make that menu include the sort of entries that are in the application menu in the GNOME Shell panel at the top of the screen. These include an entry for closing the whole application as well as setting its preferences (or options). Running the following command does just that (if it does not work as it should, try changing the single and double quotes to those understood by a command shell):

gsettings set org.gnome.settings-daemon.plugins.xsettings overrides '@a{sv} {"Gtk/ShellShowsAppMenu": <int32 0>}'

Adding in the Remove App Menu GNOME Shell extension will clean up the GNOME Shell a little by removing the application menu altogether. If, for some reason, you wish to restore the default behaviour, then the following command does the required reset:

gsettings set org.gnome.settings-daemon.plugins.xsettings overrides '@a{sv} {}'

Stopping Hiding of the Application Title Bar When Maximised

By default, GNOME Shell can hide the application title bars of GNOME applications such as Nautilus on window maximisation and this is Nautilus now works by default. Changing the behaviour so that the title bar is kept on maximised windows can be as simple as adding in the ignore_request_hide_titlebar extension. The trouble with GNOME Shell extensions is that they can stop working when a new version of GNOME Shell is used, so there’s another option: editing metacity-theme-3.xml but /usr/share/themes/Adwaita/metacity-1. The file can be opened using superuser privileges using the following command:

gksudo gedit /usr/share/themes/Adwaita/metacity-1/metacity-theme-3.xml

With the file open, it is a matter of replacing instances of ' has_title="false" ' with ' has_title="true" ', saving it and reloading GNOME Shell. This may persevere across different versions of GNOME Shell should the extension not do so.

Disabling Recursive Search

This discovery is what led me to bundle these customisations in an entry on here in the first place. In Nemo and older versions of Nautilus, just typing with the application open would lead you down a list towards the file that you wanted. This behaviour was replaced by an automatic recursive search from GNOME Shell 3.6 where the search functionality was extended beyond the folder that was open in the file manager to its subdirectories. To change that to subsetting within the open folder or directory, you need to install a patch version of Nautilus using the following commands:

sudo add-apt-repository ppa:dr3mro/personal
sudo apt-get update && sudo apt-get upgrade

The first of these adds a new repository with the patched version of Nautilus while the second combination installs the patched version. With that done, it is time to issue the following command:

gsettings set org.gnome.nautilus.preferences enable-recursive-search false

That sets the value of the new enable-recursive-search option to false for searching within an open directory. It also can be found using Dconf-Editor in the following hierarchy: org -> gnome -> nautilus -> preferences. The obsession of the GNOME project team with minimalism is robbing users of some options and this would be a good one to have by default too. Maybe the others should be treated in the same way even if you need to use Gsettings or Dconf-Editor to change them to avoid clutter. Having GNOME Tweak Tool able to set them all would be even better.

Creating a test web server using Ubuntu Server 13.04 and VirtualBox

1st September 2013

Having seen Linux Format cover tools like Vagrant and Puppet that manage virtual machines, I have been attracted by the prospect of a virtual web server running on my own PC. Certainly, having the LAMP software stack in a VM means that the corresponding tools don’t need to be added to a host system should its operating system need a fresh installation.

As intriguing as tools like Vagrant may be, I decided that I needed to learn a bit more about getting server instances set up in VirtualBox anyway. Thus, I went and downloaded the latest version of Ubuntu Server and gave that a go. One lesson that I learned was that Bridged Networking needs to be added to the VM before installation of the operating system unless you fancy overcoming the challenge of getting Ubuntu Server to recognise an altered or additional network interface. In my case, I added an extra adapter for the Bridged Networking and left the original in place as NAT. The reason for having Bridged Networking set up is that it allows access to the virtual web server from the host once you know the IP address and that information can be obtained by executing the ifconfig command on the virtual machine.

With the networking sorted, the next step was to install the 64-bit edition of Ubuntu Server. Unlike its desktop counterpart, this is all driven by text menus but remains fairly intuitive and there is hardly anything there that you wouldn’t see with another Linux distribution. A useful addition is the addition of a menu to select the type of server services that you’d like to see installed. From this, I chose the web server and SSH options and I seem to remember that there was a database server option too. If there was an FTP server option, I would have chosen that too but it was no ordeal to add ProFTPd later on anyway.

All of this set was done through the VirtualBox GUI just to keep life more straightforward. Even so, I only selected 12 MB of video memory and was tempted to cut the overall memory back from 512 MB but leaving things be for now. However, what I have begun to do is start and stop the virtual machine from the command line since servers are headless operations anyway. With SSH enabled, there is little need to have the VirtualBox GUI going. The command for starting the server is below:

VBoxManage startvm "Ubuntu Server" --type=headless

There is a VBoxHeadless command for the same end too but VBoxManage does what I need. The startvm option is what tells VBoxManage to start the server and the virtual machine’s name is enclosed in quotes. The --type=headless ensures that no window pops up. To stop the virtual web server cleanly, a command like the following is needed:

VBoxManage controlvm "Ubuntu Server" acpipowerbutton

Again, the VBoxManage command gets used and the acpipowerbutton option ensures that a clean shutdown is performed. Not doing so results in the server not fully starting up according to my experiences thus far. Getting the virtual web server to start and stop with the host machine itself starting and stopping but this looks more complex so I plan to leave things a while before trying that experiment.

Restoring GNU Parallel Functionality in Ubuntu GNOME 13.04

31st July 2013

There is a handy comand line utility called GNU Parallel that allows you to run Linux commands on more than one CPU core at a time to perform parallel processing of the task at hand. Here is a form of the command that is similar to one that I often use:

ls *.* | parallel gm convert -sharpen 1×3 {} sharpened_images/{}

What it does is pipe a list of files in a folder to GraphicsMagick for sharpening and outputting to a sharpened_images directory. The {} in the command is where the filenames go in the sharpening command.

This worked fine in Ubuntu GNOME 12.10 but stopped doing so after I upgraded to the next version. A look on the web set me to running the following command:

parallel --version

That produced output that included the following line:

WARNING: YOU ARE USING --tollef. IF THINGS ARE ACTING WEIRD USE --gnu.

Rerunning the original command with the --gnu option worked but there was a more permanent solution than using something like this:

ls *.* | parallel --gnu gm convert -sharpen 1×3 {} sharpened_images/{}

That was editing /etc/parallel/config with root privileges to delete the --tollef option from there. With that completed, all was as it should again and it makes me wonder why the change was made in the first place. Perhaps because of it, there even is a discussion about the possibility of removing the --tollef option altogether since it is raising more questions than it answers.

Adding Microsoft Core Fonts to Fedora 19

6th July 2013

While I have a previous posting from 2009 that discusses adding Microsoft’s Core Fonts to the then current version of Fedora, it did strike me that I hadn’t laid out the series of command that were used. Instead, I referred to an external and unofficial Fedora FAQ. That’s still there but I also felt that I was leaving things a little to chance given how websites can disappear quite suddenly.

Even after next to four years, it still amazes me that you cannot install Microsoft’s Core Fonts in Fedora as you would in Ubuntu, Linux Mint or even Debian. Therefore, the following series of steps is as necessary now as it was then.

The first step is to add in a number of precursor applications such as wget for command line file downloading from websites, cabextract for extracting the contents of Windows CAB files, rpmbuild for creating RPM installers and utilities for the XFS file system that chkfontpath needs:

sudo yum -y install rpm-build cabextract ttmkfdir wget xfs

Here, I have gone with terminal commands that use sudo but you could become the superuser (root) for all of this and there are those who believe you should. The -y switch tells yum to go ahead with prompting you for permission before it does any installations. The next step is to download the Microsoft fonts package with wget:

sudo wget http://corefonts.sourceforge.net/msttcorefonts-2.0-1.spec

Once that is done, you need to install the chkfontpath package because the RPM for the fonts cannot be built without it:

sudo rpm -ivh http://dl.atrpms.net/all/chkfontpath

Once that is in place, you are ready to create the RPM file using this command:

sudo rpmbuild -ba msttcorefonts-2.0-1.spec

After the RPM has been created, it is time to install it:

sudo yum install --nogpgcheck ~/rpmbuild/RPMS/noarch/msttcorefonts-2.0-1.noarch.rpm

When installation has completed, the process is done. Because I used sudo, all of this happened in my own home area so there was a need for some housekeeping afterwards. If you did it by becoming the root user, then the files would be there instead and that’s the scenario in the online FAQ.

Turning on autocompletion for the bash shell in terminal sessions

26th June 2013

At some point, I managed to lose the ability to have tab key based autocompletion on terminal sessions on my Ubuntu GNOME machine. Wanting it back had me turn to the web for an answer and I found it on a Linux Mint forum; the bash shell is so pervasive in the UNIX and Linux worlds that you can look anywhere for a fix like this.

The problem centred around the .bashrc file in my home area. It does have quite a few handy custom aliases and I must have done a foolish spring clean on the file sometime. That is the only way that I can explain how the following lines got removed:

if [ -f /etc/bash_completion ]; then
. /etc/bash_completion
fi

What they do is look to see if /etc/bash_completion can be found on your system and to use it for tab-based autocompletion. With the lines not in .bashrc, it couldn’t happen. Others may replace bash_completion with bash.bashrc to got a fuller complement of features but I’ll stick with what I have for now.

Installing Nightingale music player on Ubuntu 13.04

25th June 2013

Ever since the Songbird project concentrated its efforts to support only Windows and OS X, the Firefox-based music player has been absent from a Linux user’s world. However, the project is open source and a fork called Nightingale now fulfils the same needs. Intriguingly, it too is available for Windows for OS X users so I am left wondering why that overlap has happened. However, Songbird also is available as a web app and as an app on both Android and iOS while Nightingale sticks to being a desktop application.

To add it to Ubuntu, you need to set up a new repository. That can be done using the Software Centre but issuing a command in a terminal can be so much quicker and cleaner so here it is:

sudo add-apt-repository ppa:nightingaleteam/nightingale-release

Apart from entering your password, there will be prompt to continue by pressing the carriage return key or cancelling with CTRL + C. For our purposes, it is the first action that’s needed and once that’s done the needful, you can execute the following command:

sudo apt-get update && sudo apt-get install nightingale

This is in two parts: the first updates the repositories on your system and second actually installs the software. When that is complete, you are ready run Nightingale and, with the repository, staying up to date is not chore either. In fact, using the above commands brings another advantage and it is that they should in any Ubuntu derivatives such as Linux Mint.

A need to update graphics hardware

16th June 2013

Not being a gaming enthusiast, having to upgrade graphics cards in PC’s is not something that I do very often or even rate as a priority. However, two PC’s in my possession have had that very piece of hardware upgraded on them and it’s not because anything was broken either. My backup machine has seen quite a few Linux distros on there since I built it nearly four years ago. The motherboard is an ASRock K10N78 that sourced from MicroDirect and it has onboard an NVIDIA graphics chip that has performed well if not spectacularly. One glitch that always existed was a less than optimal text rendering in web browsers but that never was enough to get me to add a graphics card to the machine.

More recently, I ran into trouble with Sabayon 13.04 with only the 2D variant of the Cinnamon desktop environment working on it and things getting totally non-functional when a full re-installation of the GNOME edition was attempted. Everything went fine until I added the latest updates to the system when a reboot revealed that it was impossible to boot into a desktop environment. Some will relish this as a challenge but I need to admit that I am not one of those. In fact, I tried out two Arch-based distros on the same PC and got the same results following a system update on each. So, my explorations of Antergos and Manjaro have to continue in virtual machines instead.

To get a working system, I gave Linux Mint 15 Cinnamon a go and that worked a treat. However, I couldn’t ignore that the cutting edge distros that I tried before it all took exception to the onboard NVIDIA graphics. systemd has been implemented in all of these and it seems reasonable to think that it is coming to Linux Mint at some stage in the future so I went about getting a graphics card to add into the machine. Having had good experiences with ATi’s Radeon in the past, I stuck with it even though it now is in the hands of AMD. Not being that fussed so long there was Linux driver support, I picked up a Radeon HD 6450 card from PC World. Adding it into the PC was a simpler of switching off the machine, slotting in the card, closing it up and powering it on again. Only later on did I set the BIOS to look for PCI Express graphics before anything else and I could have got away without doing that. Then, I made use of the Linux Mint Additional Driver applet in its setting panel to add in the proprietary driver before restarting the machine to see if there were any visual benefits. To sort out the web browser font rendering, I used the Fonts applet in the same settings panel and selected full RGBA hinting. The improvement was unmissable if not still like the appearance of fonts on my main machine. Overall, there had been an improvement and a spot of future proofing too.

That tinkering with the standby machine got me wondering about what I had on my main PC. As well as onboard Radeon graphics, it also gained a Radeon 4650 card for which 3D support wasn’t being made available by Ubuntu GNOME 12.10 or 13.04 to VMware Player and it wasn’t happy about this when a virtual machine was set to have 3D support. Adding the latest fglrx driver only ensured that I got a command line instead of a graphical interface. Issuing one of the following commands and rebooting was the only remedy:

sudo apt-get remove fglrx

sudo apt-get remove fglrx-updates

Looking at the AMD website revealed that they no longer support 2000, 3000 or 4000 series Radeon cards with their latest Catalyst driver the last version that did not install on my machine since it was built for version 3.4.x of the Linux kernel. A new graphics card then was in order if I wanted 3D graphics in VWware VM’s and both GNOME and Cinnamon appear to need this capability. Another ASUS card, a Radeon HD 6670, duly was acquired and installed in a manner similar to the Radeon HD 6450 on the standby PC. Apart from not needing to alter the font rendering (there is a Font tab on Gnome Tweak Tool where this can be set), the only real exception was to add the Jockey software to my main PC for installation of the proprietary Radeon driver. The following command does this:

sudo apt-get install jockey-kde

When that was done I issue the jockey-kde command and selected the first entry on the list. The machine worked as it should on restarting apart from an AMD message at the bottom right hand corner bemoaning unrecognised hardware. There had been two entries on that Jockey list with exactly the same name so it was time to select the second of these and see how it went. On restarting, the incompatibility message had gone and all was well. VMware even started virtual machines with 3D support without any messages so the upgrade did the needful there.

Hearing of someone doing two PC graphics card upgrades in a weekend may make you see them as an enthusiast but my disinterest in computer gaming belies this. Maybe it highlights that Linux operating systems need 3D more than might be expected. The Cinnamon desktop environment now issues messages if it is operating in 2D mode with software 3D rendering and GNOME always had the tendency to fall back to classic mode, as it had been doing when Sabayon was installed on my standby PC. However, there remain cases where Linux can rejuvenate older hardware and I installed Lubuntu onto a machine with 10 year old technology on there (an 1100 MHz Athlon CPU, 1GB of RAM and 60GB of hard drive space in case dating from 1998) and it works surprisingly well too.

It seems that having fancier desktop environments like GNOME Shell and Cinnamon means having the hardware on which it could run. For a while, I have been tempted by the possibility of a new PC since even my main machine is not far from four years old either. However, I also spied a CPU, motherboard and RAM bundle featuring an Intel Core i5-4670 CPU, 8GB of Corsair Vengence Pro Blue memory and a Gigabyte Z87-HD3 ATX motherboard included as part of a pre-built bundle (with a heatsink and fan for the CPU) for around £420. Even for someone who has used AMD CPU’s since 1998, that does look tempting but I’ll hold off before making any such upgrade decisions. Apart from exercising sensible spending restraint, waiting for Linux UEFI support to mature a little more may be no bad idea either.

Update 2013-06-23: The new graphics card in my main machine is working as it should and has reduced the number of system error report messages turning up too; maybe Ubuntu GNOME 13.04 didn’t fancy the old graphics card all that much. A rogue .fonts.conf file was found in my home area on the standby machine and removing it has improved how fonts are displayed on there immeasurably. If you find one on your system, it’s worth doing the same or renaming it to see if it helps. Otherwise, tinkering with the font rendering settings is another beneficial act and it even helps on Debian 6 too and that uses GNOME 2! Seeing what happens on Debian 7.1 could be something that I go testing sometime.

A little look at Debian 7.0

12th May 2013

Having a virtual machine with Debian 6 on there, I was interested to hear that Debian 7.0 is out. In another VM, I decided to give it a go. Installing it on there using the Net Install CD image took a little while but proved fairly standard with my choice of the GUI-based option. GNOME was the desktop environment with which I went and all started up without any real fuss after the installation was complete; it even disconnnected the CD image from the VM before rebooting, a common failing in many Linux operating installations that lands into the installation cycle again unless you kill the virtual machine.

Though the GNOME desktop looked familiar, a certain amount of conservatism reigned too since the version was 3.4.2. That was no bad thing since raiding the GNOME Extension site for a set of mature extensions was made all the more easy. In fact, a certain number of these was included in the standard installation anyway and the omission of a power off entry on the user menu was corrected as a matter of course without needing any intervention from this user. Adding to what already was there made for a more friendly desktop experience in a short period of time.

Debian’s variant of Firefox , Iceweasel, is version 10 so a bit of tweaking is needed to get the latest version. LibreOffice is there now too and it’s version 3.5 rather than 4. Shotwell too is the older 0.12 and not the 0.14 that is found in the likes of Ubuntu 13.04. As it happens, GIMP is about the only software with a current version and that is 2.8; a slower release cycle may be the cause of that though. All in all, the general sense is that older versions of current software are being included for the sake of stability and that is sensible too so I am not complaining very much about this at all.

The reason for not complaining is that the very reason for having a virtual machine with Debian 6 on there is to have Zinio and Dropbox available too. Adobe’s curtailment of support for Linux means that any application needing Adobe Air may not work on a more current Linux distribution. That affects Zinio so I’ll be retaining a Debian 6 instance for a while yet unless a bout of testing reveals that a move to the newer version is possible. As for Dropbox, I am sure that I can recall why I moved it onto Debian but it’s working well on there so I am in no hurry to move it over either. There are times when slower software development cycles are better…

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