Should be possible to paste in to m/z,z pair lists without drag and
   dropping.

Should be possible to remove selected items from a m/z,z pair list

It should be possible to define the formula of a monomer on the basis
   of distinct groups (subformulas) which bear a name so that they can
   be referred to by name when defining fragmentation patterns. This
   would give enormous flexibility to define real patterns amongst
   monomers that fragment, like for example saying loose the side
   chain, or proton loss in ribose, or oxidation in ring...

Upon fragmentation, the ionization rule should be re-read from the
   XpertEdit window so that ionizations might change live. For
   example, switch from negative to positive mode in mass spec of
   oligonucleotides.

Fragmentation framework needs rework to include the case of negative
   peptide fragmentation where b ions correspond to the loss of CO_2
   until the very last monomer, which is not currently possible with
   the present for loop.

The definition of the fragmentation pattern might need some variable
   like "add the ionization rule".

for ( int i = 0, c = l.size(); i < c; ++i ) to optimize lists ?

Preset mass data when calling m/z ratio calculator from a sequence
   editor window.

Arbitrary mass search should take into account the cross-links.

When showing monomeric compositions, allow highlighting all the selected monomers into the sequence editor window.
Depending on the context, the return key should either send Find or Next in the Find sequence window.
Concept of flying modification, that would automagically apply to any oligomer hovered-on with the mouse after a 300ms delay.
