As from this very morning Firefox started opening new links in a new window instead of a tab (whether the current tab or starting a new one). I found a remedy (but no explanation as to why it started happening): Preferences > search 'tabs' and lo! "Open links in tabs instead of new windows". BUT: that was already checked. So I UNchecked it and everything is back to normal. Am I right to be puzzled or is it just my limited ability to understand English (I tremble waiting for a reply 
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