Customize the maximum width of the Firefox sidebar?

Question

I have Firefox Quantum web-browser version 57.0.2 (64-bit) in Windows 7.

The Sidebar, unfortunately, has a maximum width of about 540 pixels.

I tried to increase this constraint by going to about:config and searching for "sidebar". Then I changed the setting devtools.toolbox.sidebar.width;500 to a value of 600. Then I restarted Firefox. But it did not work.

So how can I increase the maximum width of the sidebar?

Answer 1

1. Firefox menu -> Help -> Troubleshooting Information -> Profile folder -> Open folder

2. There should be folder named chrome (all lowercased). If it's missing, create it.

3. In said chrome folder, there's userChrome.css file. If it does not exist, create it.

4. Open this file with any text editor.

5. In this file, if there is no CSS rule #sidebar, create it:

/* remove maximum/minimum width restriction of sidebar */
#sidebar-box {
  max-width: none !important;
  min-width: 0px !important;
}

6. Restart Firefox

Answer 2

Looks like this tag has had its name changed recently. The new tag is:

#sidebar-box {
    max-width: none !important;
}

Answer 3

• locate your profile folder https://support.mozilla.org/en-US/kb/profiles-where-firefox-stores-user-data -if there is no chrome folder inside download from this link http://franklion.co.uk/GEN-LINKS/chrome.zip

• edit the userChrome.css file

  /* remove maximum/minimum width restriction of sidebar */ #sidebar { max-width: none !important; min-width: 0px !important; }

reload the browser