HTML stripped from hand-coded select boxes after saving widget options

[sillybean]

I've been having problems with some select boxes in widget options. After I save changes, my options are displayed as text rather than option fields, like so:
​http://sillybean.net/downloads/widget-before-after.png

The values are stored correctly, but you can't make any further changes without reloading the widget admin page. Select boxes generated by WP functions (like wp_dropdown_categories or wp_dropdown_pages) don't seem to be affected, but hand-coded ones are -- although I can't see a difference in their HTML structures.

The ajax return (according to Firebug) looks like:

<p><label for="widget-randompostsfromcategory-3-content">Display:</label>
<select id="widget-randompostsfromcategory-3-content" name="widget-randompostsfromcategory[3][content]" />
  <option value="title" >Title Only</option>
  <option value="excerpt"  selected="selected" >Title and Excerpt</option>
  <option value="content" >Title and Content</option>
</select></p>

What actually shows up on the page:

<p><label for="widget-randompostsfromcategory-3-content">Display:</label>
<select name="widget-randompostsfromcategory[3][content]" id="widget-randompostsfromcategory-3-content"/>
Title Only
Title and Excerpt
Title and Content
</p>

For some reason the </select> tag is removed along with all the <option></option> tags.

The code above is taken from my ​Random Posts from Category plugin, but I've seen the same behavior in other widget plugins as well.

[scribu]

Are you sure you're using the right escape function?

Reopen if you can reproduce the error with a native widget.

[sillybean]

Reopening because I have never seen documentation indicating that form elements in widget options screens must be escaped. (Text, yes; form elements themselves, no.) My code looks exactly like that of the native widgets, but the select/option form fields are nevertheless incorrectly stripped.

[azaozz]

Looks like typo to me, <select> tag cannot be self-closing (like in the example).

[sillybean]

Wow, huge IDE fail! Thanks very much for spotting that. I'll close this and let the other plugin developers know what's causing the problem.