[Performance] Reduce calls to “Array.prototype.slice”

[conor-cafferkey-sociomantic]

Currently

There are several places where Array.prototype.slice is used to convert NodeList to Array.

Problem

With large datasets, using Array.prototype.slice on refs.data or refs.selectOptions is slow.

Wanted

Do not use Array.prototype.slice to convert NodeLists to Arrays. Instead use plain for (or for...of) to loop over NodeLists.