Where did you install Firefox from? Help Mozilla uncover 3rd party websites that offer problematic Firefox installation by taking part in our campaign. There will be swag, and you'll be featured in our blog if you manage to report at least 10 valid reports!

Avatar for Username

搜尋 Mozilla 技術支援網站

防止技術支援詐騙。我們絕對不會要求您撥打電話或發送簡訊，或是提供個人資訊。請用「回報濫用」功能回報可疑的行為。

Learn More

此討論串已被封存。 如果您有需要幫助，請新增一個新問題

Add-on dev: How can I edit Firefox UI CSS?

  • 2 回覆
  • 1 有這個問題
  • 1 次檢視
  • 最近回覆由 cor-el

dukevin
dukevin
more options

I'm developing an add-on for Firefox which will take the colors from the favicon of the current tab to color bits of the tab-bar dynamically.

I'm having trouble finding out how I can modify browser CSS, for example in the Browser Tool box console, this works perfectly fine: ```const activeTab = document.querySelector('.tabbrowser-tab[selected="true"] .tab-background'); activeTab.style.background = "rgb(0, 221, 255)";```

but when inputting this same code in my add-on, it cannot query that same selector (I've given it tabs and theme permissions). This also does not work as a stylesheet.

Can anyone point me to what I need to access the browser UI DOM?

I'm developing an add-on for Firefox which will take the colors from the favicon of the current tab to color bits of the tab-bar dynamically. I'm having trouble finding out how I can modify browser CSS, for example in the Browser Tool box console, this works perfectly fine: ```const activeTab = document.querySelector('.tabbrowser-tab[selected="true"] .tab-background'); activeTab.style.background = "rgb(0, 221, 255)";``` but when inputting this same code in my add-on, it cannot query that same selector (I've given it tabs and theme permissions). This also does not work as a stylesheet. Can anyone point me to what I need to access the browser UI DOM?

所有回覆 (2)

Paul
Paul
  • Moderator
  • Top 10 Contributor
more options

Hi

You may wish to ask about this issue in the add-on developers forum at:

https://discourse.mozilla.org/c/add-ons/35

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
more options

Web extensions can't access content in the user interface like the Tab bar, they can only interact with webpage content. You can't do this via an extension, this can only be done via userChrome.css.