My FFox doesn't take long to open, at least a little quicker then I.E., but as of yesterday it has changed - for no apparent reason.
I no longer have the arrow on the right hand end to show my 'bookmarks', and the 'Firefox' logo at the top left has changed to the small curled fox and a list of headings . viz File/Edit/View/History/Bookmarks/Tools/Help, so nothing's missing, just re-arranged. WTF ?
Never touched it M'Lud.