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The apt package management system often ends up uninstalling packages but leaving behind their configuration files. For many years it’s been easy to find them using the command dpkg -l | grep --perl-regexp '^rc', but it required fiddling around with shell commands to purge the packages (remove the leftover configuration files) because apt didn't support a way of filtering them by installation state. Since apt version 2.0 this is no longer the case, but I always forget the command and searching online usually turns up the old and overly complicated way of doing it.

This is a follow up to my previous article on automatically updating WordPress using wp-cli. A number of the sites that I maintain run on servers that have been upgraded to PHP 8.x, but some of their plugins and themes include deprecated code. As a result, every time that cron runs to check for updates, I get a load of PHP Deprecated warnings. Searching online suggested a few fixes, but none of them worked for me, so I developed a different workaround.

Things that didn’t work:

Every few months I have to set this up on a new machine, and it’s always very confusing because most VPN instructions are for Windows, Mac or mobile devices. Ubuntu’s GUI tool for managing VPNs is quite powerful, but not very intuitive. Here’s how to find all of the necessary options.

Quite frequently I start typing text into an HTML <input type='text'> element, then Alt-Tab to a different window to look something up, then Alt-Tab back to continue typing. Firefox automatically selects all of the text when the input field is refocused, which causes me to overwrite it because I automatically start typing  with the expectation that it will continue where I left off. Here is a partial mitigation for that:

What problem are we trying to solve here?

Views is a Drupal tool for organising blocks of information that repeat: it’s great for rows in a table, items in a list, and panels in a grid. But our project needed something that didn’t neatly fit any of these models, and in a sense was a bit of all three. So, rather than try to bend the defaults to our will and wrangle with the inevitable compromises, the obvious thing to do was create our own option.

I struggled to find a straightforward tutorial on this, so this is how I went about it.

Recently, I was setting up a Debian server on an old laptop with the sole purpose of running Draytek's VigorConnect software to monitor and manage the network on my campus (which uses Draytek switches and wireless access points). There are plenty of cloud-based management AP controller options, but I wanted a local, self-hosted option because our internet has been patchy in the past, and because I don't want any monthly license fees.

There’s a bug in the latest version of Ubuntu, whereby the XFCE4 lock screen repeatedly crashes. It’s already been fixed upstream in version 4.18.0, but as yet a fix has yet to be backported to Ubuntu. The fix is fairly simple, so I applied it to the current Ubuntu package and rebuilt it. Below are notes on how to do that.

First, edit your apt sources list to enable source download. Make sure that /etc/apt/sources.list includes the following line, uncommented (leave the other lines unchanged):

For laptops that are usually plugged into mains power, it’s a good idea to either remove the battery (if it’s removable), or limit the maximum charge. This extends the battery life, as keeping a battery fully charged all the time is not good for it. Many Windows laptops come with power saving tools to configure this, but the means of doing so are not very standardised and I haven’t seen any graphical Linux tools to manage it.

I recently switched to using an LG Gram laptop. Current Linux kernels have a bug with this series of laptops, which cause the CPU load to spike when a USB-C device is attached, which includes the power supply. The CPU load spike in turn overheats the CPU, maxes out the fan, and reduces battery life. Apparently a fix is expected from the mainline kernel soon, but in the meantime, I needed a way of mitigating it.

At the moment I'm working on a project where I need to use Windows, but don't have access to the Windows subsystem for Linux. In order to get access to Linux command line tools, I've installed Cygwin. For some reason Cygwin frequently breaks after a system reboot. Clicking on the Cygwin terminal launcher from the start menu, or from within Windows Explorer, briefly flickers as the Cygwin terminal starts and then immediately closes. There are lots of posts about similar issues on online forums, which generally involve some complex reinstallation of Cygwin, or updating the launch shortcuts.