Remove the selector template from the DOM

[pento]

This avoids any UAs accessing the elements before they're ready to be used - a misbehaving screen reader trying to read alt text prematurely, for example.

Wrapping it in a <script type="text/html"> tag should do the trick.

Props @peterwilsoncc for the suggestion.

[lucyllewy]

This can be done with the <template> tag from web-components spec, now..