Bug 34206: Tor Launcher button labels are missing (Firefox 76)

Mozilla's wizard has a bug where localized labels are not loaded because
Fluent is not initialized early enough. Apply the same workaround as
Mozilla applied in https://bugzilla.mozilla.org/show_bug.cgi?id=1625938

src/chrome/content/localePicker.xhtml

@@ -12,12 +12,18 @@
 <!DOCTYPE window SYSTEM "chrome://torlauncher/locale/network-settings.dtd">
 
 <window xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+        xmlns:html="http://www.w3.org/1999/xhtml"
         torwizard="true"
         title="&torlauncher.localePicker.title;"
         windowtype="TorLauncher:LocalePicker"
         persist="screenX screenY"
         onload="initLocaleDialog();">
 
+<!-- Work around a fluent bug in the wizard code (see Mozilla bug 1625938) -->
+<linkset>
+  <html:link rel="localization" href="toolkit/global/wizard.ftl"/>
+</linkset>
+
 <wizard id="TorLauncherLocalePicker">
   <script type="application/x-javascript"
           src="chrome://torlauncher/content/network-settings.js"/>

src/chrome/content/network-settings-wizard.xhtml

@@ -18,6 +18,11 @@
         onload="initDialog();"
         onunload="deinitDialog();">
 
+<!-- Work around a fluent bug in the wizard code (see Mozilla bug 1625938) -->
+<linkset>
+  <html:link rel="localization" href="toolkit/global/wizard.ftl"/>
+</linkset>
+
 <wizard id="TorNetworkSettings"
         defaulttitle="&torsettings.wizard.title.default;"
         buttonlabelextra2="&torsettings.copyLog;">

src/chrome/content/network-settings.js

@@ -2583,7 +2583,7 @@ function getElemValue(aID, aDefaultValue)
 
 function getButton(aButtonName)
 {
-  let dialogOrWizard = document.documentElement.firstChild;
+  let dialogOrWizard = document.querySelector("wizard");
   return dialogOrWizard.getButton(aButtonName);
 }