Scrollbar for expanded message headers

From MozillaZine Knowledge Base

Sometimes when you are viewing the expanded or full message headers for a message, there may be too many headers to fit in the window, with the result that you cannot see those at the bottom. Too add a scrollbar to the expanded headers pane so that you can all headers, you can use the Header Scroll extension.

Alternatively, you can instead add the following into your userChrome.css file:

/* Add vertical scrollbar for expanded header view */
#msgHeaderView { 
  max-height: 20em !important;
  overflow: auto !important; 

Note: in Thunderbird, using this scrollbar may cause horizontal lines to appear among the headers being displayed, but at least you will be able to see all the headers.

Another way to view all message headers is to look at the message source in plain text: to go the "View" menu and select "Message Source".

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