[SOLVED] Explore the DOM

Discussion of general topics about Mozilla Thunderbird
Posts: 103
Joined: April 19th, 2006, 6:12 am

Post Posted June 12th, 2020, 7:23 am

Hello everybody,

I searched "DOM" on the right here from the Thunderbird forum, and the answers I found were most about Firefox.

I spent a certain time, a few years ago, browsing the Thunderbird DOM to write a userChrome.css

For that I used DOM inspector and Element inspector, but that is no more up-to-date it seems.

At a moment I remember we had to find something to open in the file menu, but ... can anybody refresh my memory, and update the informations ?

It seems what I found there is not up-to-date either, it would be nice as it is well referenced :
Last edited by Gloops on June 12th, 2020, 1:02 pm, edited 1 time in total.

Posts: 4204
Joined: February 3rd, 2009, 6:29 pm

Post Posted June 12th, 2020, 8:48 am

In Thunderbird, the Browser Toolbox is called the Developer Toolbox.

i.e. Tools > Developer Tools > Developer Toolbox (ctrl+shift+i)

* set pref to true
* set devtools.debugger.remote-enabled pref to true
* set devtools.debugger.prompt-connection pref to false
* set devtools.inspector.showAllAnonymousContent pref to true

You can use the Select an iframe as the currently targeted document button to change the document.

3pane window > chrome://messenger/content/messenger.xul or .xhtml
message window > chrome://messenger/content/messageWindow.xul or .xhtml
compose window > chrome://messenger/content/messengercompose/messengercompose.xul or .xhtml
address book window > chrome://messenger/content/addressbook/addressbook.xul or .xhtml
error console window > chrome://devtools/content/webconsole/index.html

You can use the Pick an element from the page button to inspect an element.

Browser Toolbox

How do we get DOM info for userChrome in 57+ (popup example)


In Thunderbird, the Browser Console is called the Error Console.

i.e. Tools > Developer Tools > Error Console (ctrl+shift+j)

You can view the source of a chrome url using the console.

Code: Select all
(function () {
  var url = "chrome://messenger/content/messenger.xul";
  document.getElementById("tabmail").openTab("contentTab", {
    contentPage: "view-source:" + url,

Thunderbird 68 uses the messenger.xul page.
Thunderbird 78 uses the messenger.xhtml page.

Browser Console

Thunderbird 68 source

Thunderbird 78 source
Last edited by morat on December 26th, 2020, 10:43 am, edited 5 times in total.

Posts: 103
Joined: April 19th, 2006, 6:12 am

Post Posted June 12th, 2020, 12:59 pm

Got it !
"Pick an element from the page" answered the question, thank you.
Perhaps the options were already at the good values.

I wonder what the best place to put this would be.

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