The Focus Box is generated in putBottomControls() in moltab.js
Clicking "Find.." calls makePreFindSpt()

see doFind() and findIt() in jcontrol.js

doFind() [jcontrol.js] simply fetches the contents of the Find form slot and calls findIt().

findIt() [jcontrol.js]: complicated to handle all manual entries into Find slot.
	Sets toFind and toFindShown.
	Shows the HELP <<<<
  Calls doMolViewSpt("").
	makeFindSpt() is called automatically in scriptToJmol() [in top.js]
		[called by doMolViewSpt() in scripts.js]
		when toFind is not blank.

findNoHelp() [jcontrol.js] is used by occupancy and altlocs.
	Sets toFind and toFindShown.
  Calls doMolViewSpt("").

findOccupancy() [help1.js]
	calls findNoHelp()
	Refreshes occupancy help to add "Halos around:" at the top.

the displayed query and the Jmol command are separated in findIt()
toFindShown vs. find -> toFind which is used in doMolViewSpt()

toFind is an atom expression that can be selected.
toFindShown is the less technical form for display in help.
A good example of less technical is when "sequence=cgg" is found
with only one atom per residue.

toFindShown is used in help.js
including to show what has halos in Contacts

see doFind() and findIt() in jcontrol.js

makeFindSpt() is called automatically in doMolViewSpt() when
toFind is not blank.

In makeFindSpt() (scripts.js), halos are displayed on
  select (toFind);

In Contacts, after Halos is checked, selectedFound is set equal to toFind,
signalling that toFind is now part of the target.
The target selection script selects selectedFound and not hydrogen.
The help shows "Halos: " + toFindShown.
The code for Halos is in changePreContactsView() in jcontrol.js.