thanks a lot, anonymous! One short link, and the world shows you the most astonishing ?machine?...your one&only computer! )
O.k., spent some time and two ore three trials - now it works as usu... - no, not unbrokenly: if I open a folder with the mentioned files/icons, there is - in a lightning - the change of icons to be seen (IE to FF).
My faint suspicion: since last week of October, I use Avira av-software; nevertheless I suppressed the splashscreen of it in registry, it is known for its teamwork with IE - and, aren't there some relations between MS-Windows and certain internet explorers?
Again, thanks for fingerpost & have a good time!!
bjoenn