Join the AMA (Ask Me Anything) with the Firefox leadership team to celebrate Firefox 20th anniversary and discuss Firefox’s future on Mozilla Connect. Mark your calendar on Thursday, November 14, 18:00 - 20:00 UTC!

This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Add top border to inacytive tabs

  • 3 cavab
  • 1 has this problem
  • 18 views
  • Last reply by PCZero

more options

What is the entry I need to add to usechrome.css to add a border to the inactive tabs in FireFox? With the default configuration, the inactive tabs blur into the menu bar. When hovered the inactive tabs changes to a darker grey and has the border added. I'd like to add the bored to all inactive tabs whether hovered or not.

What is the entry I need to add to usechrome.css to add a border to the inactive tabs in FireFox? With the default configuration, the inactive tabs blur into the menu bar. When hovered the inactive tabs changes to a darker grey and has the border added. I'd like to add the bored to all inactive tabs whether hovered or not.
Attached screenshots

Chosen solution

If you aren't looking for something that has the tab shape, just a solid line, you could add a background color on the tabs "behind" the tab line element. This uses a linear gradient (top to bottom) to start gray and switch to transparent after a few pixels:

.tabbrowser-tab {
  background-image: linear-gradient(rgba(0,0,0,.2) 3px, transparent 1px, transparent 99%);
}


Two notes:

(1) I tested with the Light theme; this color probably won't work well on other themes.

(2) I think it's a little more attractive if the top line is thinner. For example, 2 pixels on the gray band:

.tabbrowser-tab {
  background-image: linear-gradient(rgba(0,0,0,.2) 2px, transparent 1px, transparent 99%);
}
Read this answer in context 👍 0

All Replies (3)

more options

Looks this is done via this CSS code:

.tabbrowser-tab:hover > .tab-stack > .tab-background > .tab-line:not([selected=true]):not([multiselected]) {
  background-color: rgba(0,0,0,.2);
  opacity: 1;
  transform: none;
}

To apply this code for all tabs you can try:

.tabbrowser-tab > .tab-stack > .tab-background > .tab-line:not([selected=true]):not([multiselected]) {
  background-color: rgba(0,0,0,.2) !important;
  opacity: 1 !important;
  transform: none !important;
}
more options

Seçilmiş Həll

If you aren't looking for something that has the tab shape, just a solid line, you could add a background color on the tabs "behind" the tab line element. This uses a linear gradient (top to bottom) to start gray and switch to transparent after a few pixels:

.tabbrowser-tab {
  background-image: linear-gradient(rgba(0,0,0,.2) 3px, transparent 1px, transparent 99%);
}


Two notes:

(1) I tested with the Light theme; this color probably won't work well on other themes.

(2) I think it's a little more attractive if the top line is thinner. For example, 2 pixels on the gray band:

.tabbrowser-tab {
  background-image: linear-gradient(rgba(0,0,0,.2) 2px, transparent 1px, transparent 99%);
}
more options

Thank you both for your responses. Very helpful. I opted for the following...

.tabbrowser-tab {

 background-image: linear-gradient(rgba(0,0,0,.2) 1px, transparent 1px, transparent 99%);

}

This gave me exactly what I want/need! Very much appreciate your assistance.