On windows Swedish/Finnish keyboard layout left ctrl + left alt works as right alt (Alt gr). On Ubuntu this does not work by default.
For example on Windows:
LeftCtrl + LeftAlt + '7' writes the '{' character.
On Ubuntu, on Finnish layout, nothing happens.
I do not except any 'solutions' where I have to set each individual special character button combination separately.
It would probably help if I new what the term 'chooser' means.
BTW: holding down alt gr and sliding my finger over all number keys gives:
1@£$5‚{[]}
1 is not supposed to give anything but 5 should give the euro character which I am now unable to write.