The fix was to go into YaST and upgrade flash-player (I think that reestablishes connections to firefox). There were also other pieces of "equivalent" software - none of them worked correctly (swfdec, gnash). After deinstalling those, I was left with flash alone, which works as expected except the images seem a tad darker than before the Firefox upgrade which started all this...

What I have now installed is: flash-player, libflashsupport, libswfdec (I should probably remove that), and swftools.