linux

Updating Thunderbird from 78 to 91 on Ubuntu

As you may know, I am a long user of an Ubuntu-flavored operating system (Kubuntu). So as I need a stable system, I usually stick with the Long Term Support (LTS) releases. Currently, my laptop runs Kubuntu 20.04.

At my new working place, people actively use calendar/email facilities. Hence, I have to start using an email client that supports this functionality. Our IT support recommends using Thunderbird, and I followed their advice. As usual in Linux distros, I have installed a Thunderbird version using my package manager and configured my email client according to the recommendations.

However, after I started to use it, I have faced issues in calendar functionality (e.g., its inability to synchronize event data) that were very difficult to triage. I checked some forums looking for explanations of some particular error codes and how to resolve them. There, I discovered that the calendar sub-system was improved considerably in Thunderbird 91.0. I checked my version of Thunderbird, and it was 78.13.x. After I found that, I decided to update Thunderbird. However, at that time, I did not manage to find a Personal Package Archive (PPA) or a deb file with this newer version. Therefore, I decided to wait until a new Ubuntu version (21.10) would be released because I thought it might bring Thunderbird 91. Unfortunately, this did not happen for older releases, and I decided to install Thunderbird 91 manually. In this article, I describe how I updated Thunderbird from version 78 to 91.

Tmux Manual

Until recently, I used tmux occasionally, only if I had to run some experiments on a remote server and later see the results of the execution. Basically, I used it only as a mean to execute commands in the background. If I needed to run several commands on a remote server parallelly, I used to open several terminals, connect each of them to the remote host and then switch between them.

Recently, I started working with a remote server through ssh more often and the routine, I used to, became very operation consuming. So, to improve my effectiveness, I spend several hours reading articles, watching videos and trainings how to use tmux. This article combines the knowledge I have acquired. It is also a crib for me if I forget something in the future.

Forceful Cooling in Linux

Several weeks ago during a compilation process, I noticed that my laptop became very hot under my palms. At first, I did not pay any attention to this, however, when it became uncomfortable to work I started to worry. My first thought was that the laptop got dusted and cannot remove the heat effectively. But then I noticed that I did not hear the fan noise when the load on the CPU increases, and I decided that my cooler is either broken or blocked. I was almost about to start disassembling my laptop, but luckily I decided to check the temperature using Linux utilities. There I found out that, despite I feel the laptop being hot, the sensor [thinkpad-isa-0000 -> temp1] showed that the CPU temperature was normal (showing all the time the temperature of 45°C). This looked suspicious, and I checked other sensors measurements and found out that the [coretemp-isa-0000] sensors showed more correct temperature values, which in addition reacted on load increase. In this article, I want to describe, how I forced my system to react also on the values from these additional sensors and cooled down my laptop.

Using PDFtk

When you are working with PDF documents, it is often required to merge them together, rotate some pages or select some of them, etc. This functionality is helpful when you care about the nature and want to avoid printing some pages. It is quite often when some authorities ask you to print a PDF document, sign just one page and send them back a scanned copy. In this situation, the PDFtk utility can be very useful. In this article, I describe some commands I use from time to time.