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Some must-have Firefox hidden settings

How to hide the “download finished” bubble

This is controlled by the browser.download.manager.showAlertOnComplete setting (edit it via about:config): set it to false to disable the highly annoying “download finished” popup which sloooooowwwwly appears and then diiiiiiiiisappeeeaaaars every time a file has finished downloading (this thing is particularly slow when your GPU is busy doing something else).

How to skip antivirus scanning of incoming files + don’t tag downloaded exe’s as coming from Internet

This is controlled by the browser.download.manager.scanWhenDone setting: set it to false to disable the bloody time-wasting virus scan at the end of every file download. This never caught a single virus for me anyway… Also, it makes the downloaded files bypass Windows security policy checks (the former preference browser.download.manager.skipWinSecurityPolicyChecks was merged into this one), ie when you launch a downloaded executable Windows won’t bother you with the warning popup “this program was downloaded from Internet, are you sure you want to run it?”.

How to delete words from the personal dictionary

For some reason, I find it extremely easy to accidentally add misspelled words to the personal dictionary – I guess that menu item is somewhat misplaced. On the other hand, deleting them is then a pain in the ***, notably the GUI provides no way to do this. You’ll have to manually edit the dictionary file…
It’s located in your profile folder (on Windows NT/2k/XP/Vista/Se7en, it looks like %appdata%\Mozilla\Firefox\Profiles\xxxxxxxx.default – just browse to %appdata%\Mozilla\Firefox\Profiles\ then it will be obvious -, for other OSes, check out Profile folder on MozillaZine, or even simpler go to about:support and click on “Profile Directory – Open containing folder”) and is named persdict.dat. You can edit it with any plain text editor supporting Unix line breaks (for instance Notepad++ is good, the standard Windows notepad isn’t). Make sure that Firefox isn’t running, as it will overwrite the file when you close it. Source

How to configure several profiles

Close Firefox (make sure there’s really no more firefox.exe running in the background), then relaunch it with the -profilemanager argument. On Windows, the easiest way to do is is probably to hit [Windows key]+R (for “Run”), and then type firefox.exe -profilemanager. After that, you should get the profile manager window, which should be self-explanatory enough. If you need more details, this post should be helpful.

How to prevent Firefox from trimming link URLs

That stupid feature was added when they replaced the status bar with that retarded add-on bar. Before that, when you hovered a link it’s target would show up in the status bar. As far as I remember, they then moved that preview to the address bar (with big fat huge trimming, as this is a limited and already well-filled space), and due to enough people getting upset with it, they moved it back to the bottom of the window (to the bottom-left, or when the find bar is opened (bug?), to the bottom-right), but this time above the add-on bar. BUT they didn’t remove the trimming: that URL preview is by default limited to 50% of the window’s width. Why the heck not 100%?? Anyway, to change that, go to your chrome folder (you might need to create it manually), which is located in %appdata%\Mozilla\Firefox\Profiles\xxxxxxxx.default\chrome (see the section about dictionary entries for more details and alternative OSes), then edit or create (with a plain text editor) the file userChrome.css. In this file, add the following section:
statuspanel {max-width: 100% !important;}
And voilà, when you restart Firefox link URL previews will be able to use the whole width of the window, so they shouldn’t get trimmed often, then…

How to decrease the minimum tab width

As in the previous tip, you need to create/edit userChrome.css. Add the following code (edit sizes as you wish):
.tabbrowser-tab[fadein]:not([pinned]) {
min-width: 15px !important;
max-width: 250px !important;}

How to force Firefox to display the full URL in the address bar

By this I mean, the real full URL, including the bloody http:// part. Well, I long thought this was impossible, but eventually a setting was created for this! In about:config, just set browser.urlbar.trimURLs to false. The change will be immediately visible! 🙂

How to hide all tab close buttons but the one on the active tab

I used to control this with the Tab Mix Plus extension, but clearly that’s overkill just to edit a simple setting… In about:config, just set browser.tabs.closeButtons to 0. The possible values are:
“0”: only show a close button on the currently selected browser tab
“1”: show a close button on all opened tabs
“2”: don’t show any tab-close button anywhere
“3”: only show a tab-close button at the end of the tab row

How to make Firefox Goolge-free

See How to eradicate Google from Firefox on Leave Google Behind. Long story short (just the steps, to make sure you don’t forget any):
1) Turn off “safe browsing”: this is the most sneaky one: with this “feature”, enabled by default, Firefox will send behind your back the URL of every site you visit to Google…
2) Disable geolocalisation: very sneaky too, this uses Google’s services to locate you (more specifically this URL: https://www.googleapis.com/geolocation/v1/geolocate?key=%GOOGLE_API_KEY%)
3) Change your default search engine in the search bar (quite obvious)
4) Change the search engine in location bar search. Quite obvious too, Firefox can be a bitch with that: it will detected that the default search engine was modified, and at some point (like, a few days later) it will pop a big button (easy to click on accidentally) to put Google back there. Alternatively you can just disable location bar search (keyword.enabled = false)
5) Last but not least: change your homepage…

Well, that’s all for today… Those are pretty much all the dirty hacks I need to perform when dealing with a new Fx install, apart from the ever changing extensions.checkCompatibility mess. Keeping them on a single page should make my life easier the next time I need them…

Late updates

2017-10-07 – How to disable lazy loading

In their permanent race to try and match Big Brother Google’s Chrome speed, Firefox added lazy loading for tabs, enabled it by default, and didn’t think it would be wise to make it easy to disable this horrible shit. I guess it’s nice on a really slow computer, but on a fast one it just means you’ll waste time every time you switch to a not-yet-displayed-during-this-session tab. Still it can be disabled in about:config by setting those to false:
browser.sessionstore.restore_on_demand
browser.sessionstore.restore_tabs_lazily
(hopefully they won’t change it again soon, the second setting was added after the first, which it broke, already :s)

Posted in Firefox.


2 Responses

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  1. David says

    To disable lazy loading in Firefox 47+:
    – open about:config
    – set browser.sessionstore.restore_on_demand to false

  2. David says

    Also, the -profilemanager argument can be replaced with just -p



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