Is your browser capable of displaying AVIF images? Here comes a fast answer using a <picture> tag. If your browser can display AVIF files, it will. Else a fallback JPEG picture will be used: Summary • Which browsers are capable of […]
Author Archive: Johannes
How to remove TLSv1.0 / 1.1 and enable TLS 1.3 in Nginx …
… on Ubuntu 18.04 or 20.04 In January 2020, SSL Labs started to downgrade ratings for websites still using TLS 1.0 and TLS 1.1 Protocols. In this tutorial we will: Disable TLSv1.0 and TLSv1.1 and enable TLSv1.3, Enable HTTP/2 if […]
How to Sync Fonts Between Linux Devices
This small guide is about syncing fonts between two or more Linux devices, for example one laptop and one desktop computer, both running any Linux distribution. More specifically, I use this method to sync fonts I downloaded via the Google […]
How to insert Google Charts in WordPress
Inserting charts in WordPress posts or pages is not so easy it could be. There are indeed some plugins to simplify your life, but they are mostly not up to date or somewhat not satisfying: ChartBoot for WordPress is the […]
Google Charts vs NVD3 vs Chart.js – Part 2
Here is the second part of my search of the best free-to-use charting library. Part 1 was a comparison of horizontal bar charts rendered with Google Charts and NVD3 (Chart.js doesn’t support horizontal bar charts). Example 2: line chart The […]
Google Charts vs NVD3 vs Chart.js – Part 1
A few days ago I wrote a post on how to add Google Charts in WordPress. The method I describe can also be used to insert NVD3 or Chart.js graphics. As I’m starting a new website on ethical banking, I’m […]
Vantage WordPress Theme – Remove the footer
If you run the Vantage theme on WordPress, you’ll notice the “A SiteOrigin Theme” footer. If you want to get rid of it, remove it, delete it, here is how to do it. First, create a child theme. In your […]
WordPress: remove links to images
WordPress default settings are somewhat awkward: if you insert an image (or any picture or media) in a post, the inserted image will link to itself. A visitor who reads your post will see a “hand pointer” when his mouse […]
Twenty Fifteen WP theme: the right way to remove post dates and author
If you’re trying to remove the post dates and author in WordPress Twenty Fifteen theme, you could just add the following code to the style.css file of your child theme: .entry-footer { display:none !important; } An awful lot of WordPress […]
How to add a new domain/website to a WordPress network (multisite)
In this post you’ll find how to add a new site with a new domain name to your existing WordPress network (aka multi-site installation). What you want: Add a new site to your WordPress network – your new site has […]
How to set up automatic updates on Ubuntu Server 18.04 or 20.04
This guide explains how to configure automatic updates in Ubuntu Server 18.04 “Bionic Beaver” or Ubuntu 20.04 “Focal Fossa” This tutorial is based on the following official Ubuntu Documentation article: Ubuntu Server Guide » Package Management » Automatic Updates Step […]
How to install a LEMP stack on Ubuntu Server 18.04 or 20.04
Introduction This guide shows how to get a full LEMP software stack installed on Ubuntu Server 18.04 “Bionic Beaver” or 20.04 “Focal Fossa”. The LEMP stack can later be used to set up a CMS like WordPress, Joomla or Drupal. […]
Ubuntu: resolve the “perl: warning: Setting locale failed” problem
Are you running Ubuntu 14.04 or 16.04 desktop or server edition, and getting warning or errors when installing software via apt-get or aptitiude? Here is a typical error message
XMind doesn’t start on Linux (Eclipse Error)
Problem: After a crash on Linux Mint, the mind mapping program XMind would not start. When executing XMind, the program displays a dialog with the following error message
How to edit metadata via the command line with ExifTool
In a previous post, I tried to find a metadata editor with a graphical user interface on Linux. The best solution, DigiKam, is designed for KDE. The second best option, XnView, is perfectible and not free software. As a Linux […]
How to edit image metadata on Linux
Image metadata is a complex field with multiple standards, the most important among them being Exif, IPTC-IIM and XMP. In this guide I try to find a solution to edit (read, modify, remove) image metadata (jpg, png, …) on Linux, […]
The Fairphone 2, Free Software and alternative operating systems
The Fairphone 2 is made by a certified B-Corporation based in Amsterdam, The Netherlands. The Fairphone 2 is probably the world’s fairest and greenest piece of advanced consumer electronics. Here is why the Fairphone should matter to anyone interested in […]
Free backup plugins for WordPress Multisite
This post is about free backup plugins for WordPress Multisite installations. The web is full of really useless “greatest backup plugins” and “best WordPress backup” lists, as these ignominiously mix up paid and free plugins. Moreover, they hardly write a […]
How to Install Firefox 102 on Linux Mint, Ubuntu, Debian, CentOS, Fedora…
… or any other Linux distribution. Last updated on June 29, 2022 Photo: janeb13 / Pixabay, Pixabay License This how-to explains how to install Firefox on Linux, with or without replacing an existing Firefox installation. Firefox 102 was officially released on June […]
How to install LibreOffice 7.3 on Linux Mint, Ubuntu, MX Linux, Debian…
Last updated on March 3, 2022 This article describes how to install LibreOffice 7.3 on Debian/Ubuntu-based Linux distributions, such as Linux Mint, MX Linux, Ubuntu and derivatives. LibreOffice 7.3 was officially released on February 2, 2021 LibreOffice 7.4 will probably […]
Multimedia, codecs, MP3 & DVD support on CentOS, Scientific Linux or RHEL
This tutorial details how to install full multimedia support, media codecs, MP3 & DVD support on Red Hat Enterprise Linux (RHEL) and its derivatives CentOS, Scientific Linux, Oracle Linux, ClearOS, … This howto assumes that you already installed RPMforge. To […]
How to change the default application for a type of file on Linux
This howto explains how to change the default program to open all files with a given extension on Linux Mint, Ubuntu, Debian, and most Linux distributions. It also details how to change the default application for a batch of filetypes, […]
Sudo on CentOS / Scientific Linux / RHEL
This short howto is about setting up sudo on Red Hat Entreprise Linux and its derivates CentOS and Scientific Linux. It also gives a quick introduction on using the vi text editor through visudo. Becoming root: su & sudo CentOS, […]
10 reasons not to use Hotmail
Did you ever try to explain to a friend why he or she shouldn’t use Hotmail? There are many good reasons to avoid Microsoft’s services, but these reasons are not so easy to explain in a clear and unambiguous way. […]
Install DVD support (libdvdcss) on Debian or Ubuntu
On Linux, DVD support is provided through the libdvdcss or libdvdcss2 packages. Some distributions already include these packages (Linux Mint, Kodi/XBMC), but most don’t. Distributions without pre-installed DVD playing capabilities are Debian, Ubuntu, SUSE Linux, Fedora, … In earlier Ubuntu […]
Install VirtualBox on CentOS / RHEL / Scientific Linux
This how-to is about installing VirtualBox on CentOS. Provided instructions should also work on Scientific Linux and Red Hat Enterprise Linux (RHEL). It is possible to install VirtualBox from rpm packages, which can be downloaded on the VirtualBox Linux downloads […]
Install Flash Player directly from Adobe on Linux Mint, Ubuntu, …
Adobe Flash Player freezes constantly on my Ubuntu installation, sometimes crashing Firefox. Most of the time though, Firefox freezes for about a minute (the window gets darker) and “recovers”, but is still not playing Flash content or Youtube videos. Flash […]
Older archived articles
Ubuntu & NVIDIA: external monitor, rotation, … (.pdf) January 2011: This how-to describes how to configure external monitors with the “NVIDIA X Server Settings” utility and enable rotation with RandRRotation. A new application background in OpenOffice Writer (.pdf) July 2009: […]
How to install LibreOffice 3.3 on Ubuntu Linux
This article describes how to install LibreOffice on Linux. The installation may be based on the official .deb packages (installs without replacing OpenOffice.org) or based on the LibreOffice ppa (replaces OOo). This how-to is for debian based Linux distributions, such […]