The APL bar can be used with Dyalog APL in Jupyter classic notebook, but not in Jupyter lab

[EmmanuelCharpentier]

Possibly germane to #20, but not identical : The APL bar is quite useful in Jupyter's classic notebook, but not in the Lab notebook : in the latter, neither the "prefix" method nor the two-chars-Tab bethod work ; I can still click a symbol in the bar to get it insterted in the active window, but this is painful (to remain polite...).