test

Clear snap folder: /var/lib/snapd/snaps

https://askubuntu.com/questions/1000177/is-the-snap-core-folder-needed

`sudo apt purge snapd ubuntu-core-launcher squashfs-tools`

`https://unix.stackexchange.com/questions/130786/can-i-remove-files-in-var-log-journal-and-var-cache-abrt-di-usr`

    $ journalctl --disk-usage
    journalctl --vacuum-size=500M

`D3 with Python in Jupyter:`

`https://livingwithmachines.ac.uk/d3-javascript-visualisation-in-a-python-jupyter-notebook/`

`https://nbviewer.jupyter.org/github/bokeh/bokeh-notebooks/blob/master/quickstart/quickstart.ipynb`

# `Install equalizer on Ubuntu 20.04`

`https://ubuntu-mate.community/t/equalizer-for-ubuntu-20-04-lts/22218`

`sudo apt install -y pulseeffects lsp-plugins`

# `Execute JNLP files in Linux`

`https://linux-tips.com/t/execute-jnlp-files-in-linux/252`

$ sudo apt-get install icedtea-netx

$ sudo apt-get install icedtea-plugin

`$ javaws filename.jnlp`

# `Take Screenshot`

`Druck`

`Shift + druck for selecting area`

# `Install writer2latex in Ubuntu`

`$` `sudo apt update`

`$` `sudo apt install writer2latex`

`http://writer2latex.sourceforge.net/index15.html`

`Specific instructions for Ubuntu: To install Java and Java support in LibreOffice, open a terminal window and type`

`$` `sudo apt-get install default-jre`

`$` `sudo apt-get install libreoffice-java-common`

`https://superuser.com/questions/1192004/why-unable-to-install-writer2latex-1-4-on-ubuntu`

`try in command line`

`$` `sudo apt-get insall libreoffice-writer2latex`

`if not working install java if not already installed`

`$` `sudo apt-get install default-jre`

# `Latex topics` `in Ubuntu`

\usepackage{hyperref}

File `pdftexcmds.sty' not found.

tlmgr install pdftexcmds

https://tex.stackexchange.com/questions/73016/how-do-i-install-an-individual-package-on-a-linux-system

$ which tlmgr

→/usr/bin/tlmgr

$ sudo /usr/bin/tlmgr install pdftexcmds

Issue: “tlmgr: user mode not initialized, please read the documentation!”

https://tex.stackexchange.com/questions/137428/tlmgr-cannot-setup-tlpdb

$ tlmgr init-usertree

https://tex.stackexchange.com/questions/158700/latex-cant-find-sty-files-altough-packages-are-installed-texlive-ubuntu-12?rq=1

$ locate caption.sty

# `Latex` `export with writer2latex (v1.6.1)`

- `By using the following settings, a .tex file could be exported, but there were issues using \usepackage{hyperref} and \usepackage[pdftex]{``graphicx``} ==> these commands in the preamble had to be commented out or replaced by \usepackage{``graphicx``}`

``

# `interactive mode with Juptyer Notebooks`

`Issue:`

`@interact and @interactive decorators did not update figures/etc.`

`Solution` `(not working)``:`

`https://stackoverflow.com/questions/36351109/ipython-notebook-ipywidgets-does-not-show`

`$ pip install ipywidgets`

`$ jupyter nbextension enable --py widgetsnbextension`

# `Using Ctrl+V to paste unformatted text by default`

https://superuser.com/questions/73450/using-ctrlv-to-paste-unformatted-text-by-default-in-openoffice-orgs-calc

You can also just switch the assigned keys from Paste to Paste Unformatted, and from Paste Unformatted to Paste. I've done this in version 6.4. I haven't tested the idea in Calc or any other module.

What you want to do is change the keystrokes that are associated with the “Paste Unformatted” and “Paste” commands. You do this using the Keyboard Customization tool.

Start by choosing Tools –> Customize. When the dialog box appears, select the “Keyboard” tab. A dialog box containing 4 panels and some control buttons appears. The top panel contains a list of every key the system allows modifying along with the command that key performs. For example, pressing `F2` starts a formula expression; `F11` invokes the styles panel.

In the Category panel, lower left corner, scroll down and highlight the Edit Category.

In the Function Panel, scroll down, and highlight Paste. The Keys panel displays "Ctrl+Shift+V". Highlight that keystroke and click the Delete button (upper right). Leave this Function unassigned for the moment.

Now highlight the Paste Unformatted Text item in the Function box. The Keys panel will display "Ctrl+V". Click Delete for this key. Now neither function has a keystroke associated with it.

To associate Ctrl+Shift+V with the Paste Unformatted Text Function, go to the Shortcut Keys panel and highlight the Ctrl+Shift+V option. Click the Modify button. "Ctrl+Shift+V" now appears in the Keys panel on the lower left.

Go back to the Paste option in the Function panel. Find "Ctrl+V" in the top Shortcut Keys panel, highlight it and press the Modify button on the right. "Ctrl+V" appears in the Keys panel on the lower left.

Click OK. Your two paste functions are now associated with the keystrokes in the way you want them.

# lAdd repository and install from this source

## Lutris (games for Linux)

https://lutris.net/downloads/

$ sudo add-apt-repository ppa:lutris-team/lutris

$ sudo apt update

$ sudo apt install lutris

install Epic Games Store from: https://lutris.net/games/epic-games-store/

Install game on Windows, but run it with Lutris & share savegames:

https://www.reddit.com/r/linux_gaming/comments/k0qxcj/is_it_possible_to_use_lutris_for_installed_games/

so the comamnd would look like thsi if you're inside the wineprefix in the above location:

ls -s ./ /windows/c/Users/You-Handsome-Guy/AppData/MyGames/My-Awesome-Game-Saves/

This way you should be able to play the game with shared save game on both systems just fine without making them interfering with each other except of the actual game files.

Problem with missing fonts on UI buttons in Rimworld:

https://www.reddit.com/r/RimWorld/comments/oo9hbo/missing_fonts/

solved by installing Arial fonts via winetricks

where to find wine savegames, e.g. for RimWorld:

/home/bora/.wine/drive_c/users/bora/AppData/LocalLow/Ludeon Studios/RimWorld by Ludeon Studios

## Install Steam on Ubuntu

https://itsfoss.com/install-steam-ubuntu-linux/

sudo apt install steam-installer

# Clear Spotify cache

https://superuser.com/questions/649208/clearing-spotify-cache-to-recover-disk-space

By default, Spotify limits its cache to 10% of your free space, which means the default setting should be okay—but if you've changed it, you could run into disk space problems. All you need to do is delete the files in the following folder (for your platform):

Windows: C:\Users\USERNAME\AppData\Local\Spotify\Storage

OS X: /Users/USERNAME/Library/Caches/com.spotify.client/Storage/

Linux: ~/.cache/spotify/Storage/

Installed with Snap on Ubuntu this config file for me was found at ~/snap/spotify/current/.config/spotify/prefs

Add or modify the line starting with storage.size to the number of megabytes you want the cache to use. For example:

storage.size=512

# activate standby mode for hdd on RaspberryPi

https://medium.com/@tamashudak/spin-down-hdd-with-raspberry-pi-using-hd-idle-7709e6c921f8

https://maker-tutorials.com/raspberry-pi-festplatte-automatisch-standby-hdparm/

https://ittweak.de/raspberry-pi-usb-fesplatte-in-standby-ruhemodus-idle-setzen/

https://superuser.com/questions/937480/does-the-raspberry-pi-2-put-usb-external-drives-to-sleep-when-not-in-use-for-a-w

# Install Tor browser

https://linuxize.com/post/how-to-install-tor-browser-on-ubuntu-20-04/

Add the Tor browser launcher PPA repository :

$ sudo add-apt-repository ppa:micahflee/ppa

Install the Tor browser launcher package:

$ sudo apt update

$ sudo apt install torbrowser-launcher

The Tor browser can be launched either from the command line by typing torbrowser-launcher or by clicking on the Tor Browser Launcher icon (Activities -> Tor Browser).

If you want to uninstall the Tor browser, remove the installed package with the following command:

$ sudo apt remove torbrowser-launcher

## specify exit node:

https://www.wikihow.com/Set-a-Specific-Country-in-a-Tor-Browser

https://tor.stackexchange.com/questions/733/can-i-exit-from-a-specific-country-or-node

need to edit torrc file located in following folder:

/home/bora/.local/share/torbrowser/tbb/x86_64/tor-browser_en-US/Browser/TorBrowser/Data/Tor

add following line into file if not existing yet:

ExitNodes {TR}

# Write Linux image onto USB drive

## Using balena etcher and link to image:

Ubuntu mirrors: https://launchpad.net/ubuntu/+cdmirrors

- copy link to one of the iso image, e.g. https://ftp-stud.hs-esslingen.de/pub/Mirrors/releases.ubuntu.com/21.10/ubuntu-21.10-desktop-amd64.iso

- paste link into balena GUI →

advantage of providing only link to iso and not download the image is that nothing has to be saved on the PC

# Install and Uninstall software on Ubuntu

## Kicad

Quick installation of kicad:

$ sudo apt-get update

$ sudo apt-get install kicad

https://www.thelinuxfaq.com/ubuntu/ubuntu-17-04-zesty-zapus/kicad?type=uninstall

$ sudo apt-get remove kicad

Uninstall kicad including dependent package: $ sudo apt-get remove --auto-remove kicad

If you use with purge options to kicad package all the configuration and dependent packages will be removed: $ sudo apt-get purge kicad

If you use purge options along with auto remove, will be removed everything regarding the package, It's really useful when you want to reinstall again: $ sudo apt-get purge --auto-remove kicad

# Blender

https://docs.blender.org/manual/en/latest/getting_started/installing/linux.html

Install from Snap

$ snap install blender

# Use YubiKey

## Installation of yubikey manager

https://support.yubico.com/hc/en-us/articles/360016649039-Enabling-the-Yubico-PPA-on-Ubuntu

sudo add-apt-repository ppa:yubico/stable && sudo apt-get update

YubiKey Manager (CLI): sudo apt install yubikey-manager

YubiKey Personalization Tool: sudo apt install yubikey-personalization-gui

libpam-yubico: sudo apt install libpam-yubico

libpam-u2f: sudo apt install libpam-u2f

alternatively: run the YubiKey manager AppImage!

## Touch triggered OTP

https://developers.yubico.com/Developer_Program/Guides/Touch_triggered_OTP.html

Authentication with Mobile Platforms

https://developers.yubico.com/Mobile/

Applications supporting YubiKeys

https://www.yubico.com/de/works-with-yubikey/catalog/?sort=popular

Ubuntu Linux Login Guide – U2F

https://support.yubico.com/hc/en-us/articles/360016649099-Ubuntu-Linux-Login-Guide-U2F

Secure Windows with strong authentication

https://www.yubico.com/products/computer-login-tools/

Yubico Login for Windows Configuration Guide

https://support.yubico.com/hc/en-us/articles/360013708460-Yubico-Login-for-Windows-Configuration-Guide

Associating the YubiKey with Websites (Services)

https://support.yubico.com/hc/en-us/articles/360013778879-Associating-the-YubiKey-with-Websites-Services-

Yubico Authenticator

https://www.yubico.com/products/yubico-authenticator/

How to register your spare key

https://support.yubico.com/hc/en-us/articles/360021919459-How-to-register-your-spare-key-

Using Your YubiKey with Authenticator Codes

https://support.yubico.com/hc/en-us/articles/360013789259-Using-Your-YubiKey-with-Authenticator-Codes

Understanding YubiKey PINs

https://support.yubico.com/hc/en-us/articles/4402836718866-Understanding-YubiKey-PINs

Basic YubiKey Troubleshooting

https://support.yubico.com/hc/en-us/articles/360013707540-Basic-YubiKey-Troubleshooting

Using Your YubiKey with KeePass

https://support.yubico.com/hc/en-us/articles/360013779759-Using-Your-YubiKey-with-KeePass

4d24a4ae6c32c56060d1f52d76f47aade44f885f

KeeChallenge (A plugin for KeePass2 to add Yubikey challenge-response capability.)

https://richardbenjaminrush.com/keechallenge/

# How to run an AppImage

https://appimage.org/

Make it executable

$ chmod a+x Subsurface*.AppImage

and run!

$ ./Subsurface*.AppImage

# Install KeePass

https://keepass.info/download.html

https://sourceforge.net/p/keepass/discussion/329220/thread/17d1bd26/

sudo apt-add-repository ppa:jtaylor/keepass

sudo apt-get update

sudo apt-get install keepass2

# Get root access for copying files to /usr/share/...?

https://askubuntu.com/questions/10435/get-root-access-for-copying-files-to-usr-share

/usr/ is owned by the root account so to write files in there you need to write them as root. Two methods (there are undoubtedly more but here are the two main ways for most users):

1. Press Alt+F2 to get a run dialogue and in that type gksu nautilus. This will open up a file browser window running as root. Copy your files across but be careful, you can nuke the system like this.

2. A much more direct method is just loading up a terminal and writing:
   sudo cp -R /path/to/files/you/want/copied/ /copy/to/this/path/
   (the -R is just there to recursively copy directories)

If you ever want to fire off multiple commands as root without prepending them all with sudo you can run sudo -i or sudo su and you'll get a root terminal. But again, be careful what you do.

OR:

sudo gnome-terminal

OR:

https://www.how2shout.com/linux/open-ubuntu-file-manager-as-root-user/

sudo nautilus