Accessibility - labels aren't clickable

[edent]

The "Search subscribers" page has this searchbox:

Clicking on the labels doesn't toggle the checkboxes. The HTML is currently:

<label for="unconfirmed">
   Show only unconfirmed subscribers:
  <input type="checkbox" name="unconfirmed" value="1">
</label>

In order to work, the <input> needs to have an id which matches the label's for. For example:

<input id="unconfirmed">

I'd like to create a PR to fix that in:

phplist3/public_html/lists/admin/users.php

Lines 323 to 332 in edbdc4f

	$filterpanel .= sprintf('<form method="get" name="listcontrol" action="">
	<input type="hidden" name="page" value="users" />
	<input type="hidden" name="start" value="%d" />
	<input type="hidden" name="find" value="%s" />
	<input type="hidden" name="findby" value="%s" />
	<label for="unconfirmed">%s:<input onclick="if (this.checked && form.confirmed.checked) form.confirmed.checked=false" type="checkbox" name="unconfirmed" value="1" %s /></label>
	<label for="blacklisted">%s:<input onclick="if (this.checked && form.nonblacklisted.checked) form.nonblacklisted.checked=false" type="checkbox" name="blacklisted" value="1" %s /></label>
	<div class="clearfix"></div>
	<label for="confirmed">%s:<input onclick="if (this.checked && form.unconfirmed.checked) form.unconfirmed.checked=false" type="checkbox" name="confirmed" value="1" %s /></label>
	<label for="backlisted">%s:<input onclick="if (this.checked && form.blacklisted.checked) form.blacklisted.checked=false"type="checkbox" name="nonblacklisted" value="1" %s /></label>',