These tips for using Mozilla Firefox were originally spread over multiple blog posts, but they are rather short and also pretty old (so maybe not valid anymore), that’s why I now collected them all on this single page…

Automatically save bookmarks to an HTML file

(Originally posted on 2020-12-20)

I recently found out about an interesting feature of Mozilla Firefox, that is not new, but of which haven’t heard before: Firefox can be configured to automatically save its bookmarks as an HTML file to a specific folder on exit.

Although I know (and make use of) the capability to save the bookmarks explictly from the library ¹), and I also dimly remember having read about the fact that Firefox backs up the most recent bookmark files ², I didn’t know about this ‘auto save’ gimmick.

Here’s how to set it up:

1. Enable the feature: Type about:config in the address bar and press Enter (select “Accept the Risk and Continue”).
2. Enter browser.bookmarks.autoExportHTML in the search bar at the top.
3. Toggle the value to True by clicking the button at the right.
4. Create a new configuration preference: Enter browser.bookmarks.file in the search bar at the top.
5. Select String and click the Add/[+] button at the right.
6. Enter the full path of the location where you want to save the file, e.g. C:\Users\<username>\Documents\Bookmarks Backup\Bookmarks.html (plain text, no need for enclosing quotes, even with spaces in the path).
7. Click the Save/Checkmark button and close the configuration tab again.
8. Firefox needs to be restarted for the changes to take effect.
   After that, your file will be saved there everytime you close Firefox.
   Note that only one file is created and is being overwritten each time that you close the browser!

Show Close Button On Tabs

(Originally posted on 2014-04-07)

1. Enter about:config in the address bar.
2. Search for browser.tabs.closeButtons
3. Possible values are:
   • 0: Only the currently active tab displays a close button.
   • 1: Each tab has its own close button (Default).
   • 2: Tabs without close button, a tab can only be closed via context menu or Ctrl+W.
   • 3: Only one button (on the right) for all tabs; acts on the currently active tab.

Source: c’t 2009, #23, S. 166.

Delete Entries From The Search Bar

(Originally posted on 2014-04-07)

1. Click into the search bar.
2. Enter the first characters of the term that you want to delete; use the up-/down-arrow if necessary.
3. Select the term and press the Delete key.

Source: c’t 2009, #23, page 166.

Display Tabs Below The Address Bar Again

(Originally posted on 2014-04-07)

1. Open Mozilla Firefox and enter about:config into the address bar, accept the warning.
2. Search for browser.tabs.onTop and set it to False.

New Tab Settings

(Originally posted on 2014-04-07)

1. Enter about:config in the address bar.
2. Search for browser.tabs.insertRelatedAfterCurrent
3. The value true (default) means new a new tab will be inserted directly after/right to the original tab, instead at the end.
4. In order to force all links that open in a new window to load in a background tab, set browser.tabs.loadDivertedInBackground to true.

Rendering Modes

(Originally posted on 2014-04-07)

Disclaimer: This information is based on Firefox 4, now Firefox 28 is the current version (2025: Version 138.0.1), so maybe it’s obsolete…

1. Enter about:config in the address bar.
2. Search for gfx.font_rendering.cleartype_params.rendering_mode.
3. Possible values are:
   • -1: Firefox default
   • 0: default
   • 1: aliased
   • 2: GDI Classic
   • 3: GDI Natural
   • 4: Natural
   • 5: Natural Symmetric