Firefox: optimize its settings

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With a couple of changes in the settings, you can improve the performance of Firefox in Ubuntu or Linux Mint. These tweaks will make this fine web browser leaner and cleaner.

Menu bar visible in Firefox

1. Unfortunately, the menu bar of Firefox isn't visible by default. Very annoying, but this is how you can fix that:

Firefox menu button (with the three horizontal dashes on it, top right) - Customize - Show/Hide Toolbars - check: Menu Bar

Make Firefox cleanse itself automatically upon quitting

2. Improve your privacy: you can configure Firefox to cleanse itself automatically, upon quitting. All cookies and history are being deleted then. Furthermore, you can limit the tracking that some websites do to follow you.

The price you pay is a small decrease in user friendliness, but it's not much. The privacy gain is huge, and outweighs this price by far.

You can do it like this:

Firefox menu button (with the three dashes on it) - Preferences - Privacy

a. Item Tracking: set it to:
Tell sites that I do not want to be tracked

b. Item History: change the setting to:
Firefox will: Use custom settings for history

c. for cookies, change the setting to:
Keep until: I close Firefox

d. Now tick the following setting:
Clear history when Firefox closes

e. Then, click the button "Settings..." (on the right of "Clear history") and tick everything, except for Site Preferences. Click OK.

f. Item Location Bar: remove the tick for: History

Close the Preferences tab and you're done.

Tip: sometimes it may come in handy to force a cleansing during your web browsing. Simply by closing Firefox and launching it anew.

Limit the storage

3. By default, Firefox can store far too much files. Limit it like this:

Firefox menu button (with the three dashes on it) - Preferences

Tab Advanced:

Tab Network - Cached Web Content:
- tick: Override automatic cache management
- set the cache to 50 MB, which is more than enough.

Click the button Clear now and then the Close button.

Disable the memory of the URL bar

4. The memory of the URL bar is more aggravating than useful, when you want to type a website address directly. An irritating busybody: "Maybe you want to type this?". Thank heaven you can disable this annoyance like this:

Type in the URL bar of Firefox:


Press Enter.

Now you're being presented with an warning. Ignore it and click on "I'll be careful, I promise!" (which is probably an attempt at humour. Sigh...)

Go to:

Double-click that line and change the value to 0.

Note: this is a user preference. Repeat it in each user account.

Disable Java and openJDK by default

5. When you've installed openJDK or Oracle Java, then it's safer to have the Java (or IcedTea) plugin in Firefox, disabled by default. Java is often under attack by criminal and malicious software and websites. Because of the nature of Java (it's platform independent), even Linux is vulnerable in this aspect.

You can enable Java / openJDK for a short while whenever you need it (usually pretty rarely). That way, your ease of use is reduced only a little bit, while your system becomes a lot more secure.

Disabling of Java in Firefox can be done like this:
Firefox menu button (with the three dashes on it) - Add-ons - click on Plugins (left side of the window) - click "Disable" for Java (or for IcedTea).

Note: this only applies to Java. There's also Javascript, which is safe. So there's no need to disable Javascript as well.

Configure Adobe Flash Player well

6. By applying the multimedia how-to you'll have installed Adobe Flash Player. You can improve its default settings, and among other things remove the relatively unknown Flash cookies.

Unfortunately most of this can only be done by a strange and unusual web based tool from Macromedia. This is how you do it:

a. Go to Adobe Flash Player Settings Manager

Note: that web page is the tool itself!

b. Now the settings manager opens with the tab Global Privacy Settings. Click here on "Always ask..." Or, if you prefer a higher degree of security, "Always deny...".

c. Now click the tab Global Storage Settings.
Put the slider at at 10 KB (otherwise it'll remember too much information in your cookies, which is bad for your privacy). This is a per-cookie maximum size.

d. Now click the tab Website Privacy Settings. Click "Delete all sites".

e. Finally, click the tab Website Storage Settings. Click "Delete all sites".

You may want to run this settings manager on a regular basis, in order to remove stored content.

Weak graphics card: disable the hardware acceleration in Firefox

7. Some older or weaker video cards have trouble because of the hardware acceleration that's on by default in Firefox. When you experience graphics problems in Firefox (delay when typing text, problems with displaying video's), disable it as follows:

Click on the button with three horizontal dashes in the top right corner - Preferences - Advanced:
remove the tick for: Use hardware acceleration when available
Close Firefox and launch it again.

(continued in the column on the right)

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Add-ons and extensions: don't turn Firefox into a Christmas tree

8. You can install a lot of add-ons (extensions) in Firefox. Some of those add-ons can be very useful.

But they have a couple of important disadvantages, because they are "applications within an application":

- they slow Firefox down, especially if there are a lot of them;
- they can cause malfunctions; both in each other and in Firefox itself;
- it has occurred: add-ons with malicious content. Don't trust them blindly.

So don't turn Firefox into a Christmas tree: don't adorn Firefox with lots of add-ons. Limit yourself to only a few add-ons, that are really important for you.

Strictly speaking, extensions and add-ons pollute the clean code of your browser. It's wise to keep the level of pollution down to an absolute minimum.

Note: watch out for add-ons that claim to make Firefox faster! Often they do more harm than good. Do not install them: even if one or two of them can really make Firefox run noticeably faster, they may damage the stability of your browser.

Test Firefox with a clean slate

8.1. For troubleshooting purposes it can be useful to test Firefox with a clean slate. So with a default profile and with no other add-ons and extensions than the default ones.

You can do that as follows:

a. Launch a terminal window.
(You can launch a terminal window like this: *Click*)

b. Now disable your current Firefox profile by renaming it. For that, copy/paste the following line into the terminal:

mv -v ~/.mozilla ~/.mozillabackup

Press Enter.

c. Then make sure that the default Firefox profile is present in your user folder. For that, copy/paste the following line into the terminal:

cp -v -r /etc/skel/.mozilla ~/.mozilla

Press Enter.

d. Close Firefox and launch it again. It should have a clean slate now.

e. Do your testing.

When you're done, you can restore the old profile like this:

f. First remove the newly created profile folder, with this terminal command (use copy/paste):
rm -v -r ~/.mozilla

g. Then restore the old profile with this terminal command (use copy/paste):
mv -v ~/.mozillabackup ~/.mozilla

h. Close Firefox and launch it again. All should be as it was before.

Run Firefox from within a secure sandbox

9. You can increase the security of Firefox greatly, when you run it from within a secure sandbox. This neat solution causes almost no loss of user-friendliness and only causes a little extra system load, while making Firefox much more secure.

You can achieve that by applying this how-to.

Enable rendering of DRM content

10. Digital Rights Management (DRM) is a nasty phenomenon. But unfortunately it's a fact of life, that some web content has been contaminated with that....

You can enable playback of DRM content in Firefox like this:

Firefox menu button (with the three dashes on it) - Preferences - Content
DRM content: tick Play DRM content

Letters too small on web pages? Increase the font size

11. You can enlarge the displayed font size like this:

Press the Ctrl key and keep it pressed (don't release it). Now hit the plus key ( + ) for as many times as you wish, until the font size that you want is achieved. Minimize: keep the Ctrl key pressed and hit the minus key ( - ). Back to default: keep the Ctrl key pressed and hit the zero key ( 0 ).

This however enlarges both text and images. That often renders images ugly. Set the enlargement therefore to "Zoom Text Only". Like this:

First make the Firefox menu bar visible (not necessary in main edition Ubuntu, because there it's by default part of the global menu in the top of your display):
Firefox panel - right-click on the right of the green plus sign - tick:
Menu Bar

In the menu bar: View - Zoom - tick: Zoom Text Only.

Note: even if you see no tick box, you can place that tick nevertheless!

On netbooks with small displays you can also use the nifty add-on Default FullZoom Level. You can install it in Firefox, like this: Firefox menu button (with the three dashes on it) - Add-ons - Get Add-ons.

The default settings of Default FullZoom Level aren't optimal. So configure it like this:
Firefox menu button (with the three dashes on it) - Add-ons - click on Extensions (left side of the window)
Default Full Zoom Level: click on Preferences.
- Then set Default FullZoom Level (percent) at 120.
- Then tick: Change default Mode to Zoom Text Only.
The other two options must also be ticked, but they should be ticked by default.

Note: be very reluctant to install add-ons in Firefox: the more add-ons, the slower Firefox becomes.

Make new tab pages empty

12. By default, when you open a new tab page, Firefox shows tiles of websites that you've previously visited. If you prefer those new tabs to show an empty page instead, you can do that as follows:

In the new tab, click the gear icon in the top right of the new tab - check: Show a blank page.

Want to get rid of polluted settings in Firefox?

13. Do you have polluted settings in Firefox (possibly because of shady add-ons), and do you wish to start anew with a clean browser? Then proceed like described in item 8.1 on this web page (right column).

Linux Mint: change the search engine of the Firefox search bar into Google

14. Linux Mint has Yahoo as default search engine in the search bar of Firefox. That's not ideal: most people prefer Google.

Mint has made it difficult to change Yahoo into Google (sigh...), but this is how you can still do that.

More tips?

15. Do you want more tips and tweaks for Ubuntu and Linux Mint? There's a lot more of them on this website!

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