Hello,
Maybe you can try something like this...
// 'FIRST', 'PRIOR', 'NEXT',
// 'LAST', 'INSERT', 'DELETE', 'EDIT', 'POST', 'CANCEL', 'REFRESH', 'APPLYUPDATES', 'CANCELUPDATES'
procedure TMainForm.UniFormReady(Sender: TObject);
var
btnName: string;
btnHint: string;
begin
btnName := 'FIRST'; //uni_dbn_xxx
btnHint := 'First';
UniSession.AddJS('Ext.ComponentQuery.query("[uname=uni_dbn_'+ btnName +']").forEach(function(el){el.setTooltip("'+ btnHint +'")});');
btnName := 'PRIOR'; //uni_dbn_xxx
btnHint := 'Prior';
UniSession.AddJS('Ext.ComponentQuery.query("[uname=uni_dbn_'+ btnName +']").forEach(function(el){el.setTooltip("'+ btnHint +'")});');
//...
end;