Under lib/javascrip-static.js, L339, get_htmlelement_size function returns 'NaN' if #page-footer is set to 'display: none'.

To reproduce:
1. Set "Appearance / Theme / Custom CSS":
#page-footer

2. Set "Site policy URL" and "Site policy URL for quests".
3. Open /user/policy.php, you shouldn't see a policy content, as "iframe" height is set 0.

The issue with el.getComputedStyle(prop); which returns "auto".

Solution:
if (val == 'auto') {
val = el.getComputedStyle(prop);
// check val for int
if (!isNaN(parseInt(val)))

}
return parseInt(val);

Cheers