It took me a while to find out how to change the file explorer application that Firefox uses when I press the “Open Containing Folder” button in the download manager.

I first tried adjusting the MIME type mappings in /usr/share/applications/defaults.list, /usr/share/applications/mimeinfo.cache, and ~/.local/share/applications/mimeapps.list, as suggested here and here. No success.

Finally, by grepping my home directory for “dolphin” (which I wanted to get rid of as default browser), I found another default mapping in ~/.config/lxsession-default-apps/settings.conf

In this file, I needed to adjust the line starting with file_manager/installed  as follows (one line!):

file_manager/installed=File Manager PCManFM,pcmanfm,system-file-manager,/usr/share/applications/pcmanfm.desktop,;

Scrollen mit der mittleren Maustaste

Setze die Option general.autoscroll in der about:config auf true.

Suchergebnisse der Location Bar einschränken

Die folgenden Schnellfilter für die Suche im URL-Eingabefeld (“Location Bar”) können in der
about:config unter dem Präfix browser.urlbar.restrict gefunden werden.
Mehrere Suchwörter müssen mit Leerzeichen getrennt werden.

  • * Microcontroller: nur Lesezeichen zeigen, die das Wort ”Microcontroller” enthalten
    • Merkhilfe: Der Asterisk sieht aus wie ein Favoritenstern
  • ^ Microcontroller: nur Einträge aus dem Verlauf zeigen, die das Wort ”Microcontroller” enthalten
    • Merkhilfe (na ja): Der Pfeil zeigt zurück in der Historie.
  • + Microcontroller: nur ”Lesezeichen” zeigen, die mit ”Microcontroller” getaggt wurden
    • Merkhilfe: Das Plussymbol sieht ähnlich aus wie ein kleines t. Oder: Tags werden angeheftet = hinzugefügt = “geadded”.

Ebenfalls nützlich könnte sein:

  • % Microcontroller: nur geöffnete Tabs zeigen, die das Wort ”Microcontroller” im Namen enthalten

Cache leeren

Shift+Click, Strg-F5 oder Strg-R (Befehlstaste-R auf dem Macintosh) drücken. Strg-F5 nicht bei Linux / KDE, da hiermit auf das 5. Fenster umgeschaltet wird.


The Java plugin for Firefox is activated if Firefox finds a symlink to in its plugins folder.

  1. Locate the plugins directory of Firefox. You may either use the per-profile or the global directory. In my case these are
  2. Locate the path to your JRE’s browser plugin:
    $ locate
  3. Remove any existing (links to) Java plugins from the plugins folders.
  4. Create a symbolic link to the plugin:
    cd /usr/lib/firefox/browser/plugins
    sudo ln -s /opt/jdk1.8.0_05/jre/lib/amd64/ .
  5. Restart Firefox and verify that the plugin is recognized by opening about:plugins .


  • [1] Original instructions

The social network SchülerVZ which is targeted at young students is going down on April 30, 2013. I wanted to save some of my friends’ photos and searched the web for some appropriate tool.

I tried the Bilderdownload v2 from and a Fotoalbum Download für StudiVZ, SchuelerVZ & MeinVZ 1.09 from both  of which did not work for me. So I needed to create a solution on my own.

Custom-Made Approach

The following description is only tested with the Altes SchülerVZ  theme. When I took a look at the HTML code around photos (<div class=”photo”>), I recognized that it is not possible to right-click a photo in Firefox and select Save Image As… because the context menu has been disabled:

<img id="photoDetailBig" oncontextmenu="return false;" 
alt="" src="[...].jpg" 

While it is perfectly reasonable that the SchülerVZ guys want to protect their users’ personal rights, in the current circumstances, I personally find it legitimate to circumvent this restriction. Disclaimer: You are responsible for your doings. Ask your friends first, if you may download their photos.

Preparations: Install GreaseMonkey

For Firefox there exists a nice add-on called Greasemonkey which allows you to execute arbitrary JavaScript code on sites of your choice. The add-on can be downloaded from the official Firefox add-on site. (Click here for immediate installation).

Installing the Userscript

After the  installation of Greasemonkey is complete, you still need the script which unlocks the context menu for photos. I uploaded the script to If the automatic installation does not work for you, you may manually install the script:

  1. Select Tools -> Greasemonkey -> New User Script…
  2. Set the name to Enable SchülerVZ Photo Download (Altes schülerVZ theme)
  3. Set the namespace to
  4. Set the includes to*
  5. Confirm with OK.
  6. Copy the whole code into the editor which pops up and save it.

When you now open up a photo, you will be able to open the context menu and save the image.