neil@parkwaycc.co.uk <neil@httl.net> has granted Stefan <stefanh@inbox.com>'s
request for superreview:
Bug 435079: Migrate Composer's New Page Settings prefs to the new prefpane
https://bugzilla.mozilla.org/show_bug.cgi?id=435079

Attachment 328536: Take 2, use browser pref observers etc
https://bugzilla.mozilla.org/attachment.cgi?id=328536&action=edit

------- Additional Comments from neil@parkwaycc.co.uk <neil@httl.net>
Did one of the versions update the editor preview if you updated the browser
colours even in non-instant-apply mode, or have I been dreaming?

>+const browserPrefsObserver = 
Nit: trailing space

>+    switch(aData)
Nit: space before (

>+  if(customColors)
Nit: space before (

>+    let isLocked = CheckLocked(buttons[i].getAttribute("id"));
Nit: .id

>+    gPreviewBGColor = color;
>+   
UpdateBgPreview(document.getElementById("editor.default_background_image").valu
e);
UpdateBgPreview is the only user of gPreviewBGColor, so you should pass it in
as a parameter rather than abusing a global. r+sr=me with that fixed.

>+    document.getElementById(previewID).setAttribute("style","color: " + color
+ ";");
Nit: space after ,