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Open new tab with middle click - SeaMonkey

From MozillaZine Knowledge Base

The option for opening links in new tabs with a middle-click (or Ctrl+click) is off by default. To turn it on:

  1. Go to Edit -> Preferences
  2. Expand Navigator (or Browser in SeaMonkey 2) in the left pane.
  3. Select Tabbed Browsing
  4. Check "Middle-click, Control+click or Control+Enter on links in a Web page".