Unable to hide page action button in Firefox 57

Question

I wanted to remove the "Page Action" button in the Firefox url, so I added the following line to my file userChrome.css:

#urlbar-page-action-button {display:none !important;}

However, nothing happened. How can I accomplish what I'm trying to do?

I am using Firefox Nightly version 57.0a1on Macbook.

Answer 1

Change #urlbar-page-action-buttonto .urlbar-page-action.

Answer 2

I had problems with your solution. It seems to be #an id selector, not a class ... etc.

You can modify the file userChrome.cssin <userprofile>/chrome/userChome.css. Check the location of your directories with about:profiles.

userChrome.css:

/* Do not remove the @namespace line -- it required for correct functioning */
@namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul");

/* -- Test to see if this file is loaded correctly -- */
/* * {background-color:red !important;} /* *emphasis* important, '!' isn't NOT in CSS */

/*
 * HTML element to hide:  
 * <image xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul" 
 * id="pageActionButton" class="urlbar-icon urlbar-page-action" role="button"
 * tooltiptext="Page actions" onmousedown="BrowserPageActions.mainButtonClicked(event);"
 * />
 *
 * element: image
 * id: pageActionButton
 * class: urlbar-icon urlbar-page-action
 */

image#pageActionButton {display:none !important;}
image.urlbar-page-action {display:none !important;}
                   /* who knows, maybe we get lucky and they change only one. */

Firefox 57.0, , " ", (, ).