<p>If you're using Opera 9.5x you may notice that our client-side <a href="http://docs.jquery.com/Plugins/Validation" rel="noreferrer">JQuery.Validate</a> code is disabled here at Stack Overflow.</p>

<pre><code>function initValidation() {
    if (navigator.userAgent.indexOf("Opera") != -1) return;
    $("#post-text").rules("add", { required: true, minlength: 5 });
}
</code></pre>

<p>That's because it generates an exception in Opera! Of course it works in every other browser we've tried. I'm starting to seriously, seriously hate Opera.</p>

<p>This is kind of a bummer because without proper client-side validation some of our requests will fail. We haven't had time to put in complete server-side messaging when data is incomplete, so <strong>you may see the YSOD on Opera much more than other browsers</strong>, if you forget to fill out all the fields on the form.</p>

<p>Any Opera-ites want to uncomment those lines (they're on core Ask &amp; Answer pages like this one -- just View Source and search for <code>"Opera"</code>) and give it a go?</p>

[{'answer_id': 8712, 'author': 'Neall', 'author_id': 619, 'author_profile': 'https://Stackoverflow.com/users/619', 'pm_score': 0, 'selected': False, 'text': '<p>I can\'t seem to reproduce this bug. Can you give more details?</p>\n\n<p>I have my copy of Opera masquerading as Firefox so the validation should be executing:</p>\n\n<pre><code>&gt;&gt;&gt; $.browser.opera \nfalse\n</code></pre>\n\n<p>When I go to the edit profile page and enter a malformed date, the red text comes up and says "Please enter a valid date". That\'s jQuery.Validate working, right? Does it only fail on certain forms/fields?</p>\n\n<p>This is Opera 9.51 on WinXP.</p>\n\n<p>Edit: testing editing on Opera.</p>\n\n<p>Edit: It also works when I comment out the "if ($.browser.opera) return;" line on a copy of the edit profile page I saved locally. I really can\'t reproduce this bug. What is your environment like? (Vista? Opera plugins?)</p>\n'}, {'answer_id': 9269, 'author': 'Jeff Atwood', 'author_id': 1, 'author_profile': 'https://Stackoverflow.com/users/1', 'pm_score': 5, 'selected': True, 'text': '<p>turns out the problem was in the</p>\n\n<pre><code>{ debug : true }\n</code></pre>\n\n<p>option for the JQuery.Validate initializer. <strong>With this removed, things work fine in Opera.</strong> Thanks to Jörn Zaefferer for helping us figure this out!</p>\n\n<p>Oh, and the $50 will be donated to the JQuery project. :)</p>\n'}, {'answer_id': 9273, 'author': 'Brendan', 'author_id': 199, 'author_profile': 'https://Stackoverflow.com/users/199', 'pm_score': 0, 'selected': False, 'text': "<p>I'm not up on .NET but I'm guessing YSOD implies uncaught errors, if that's the case then isn't relying on client-side validation alone a little risky? If not then errors that are caught can be converted to something useful for the Opera crowd - even if it is just a Screen Of Death painted white with validation grumbles ...</p>\n"}]
['https://Stackoverflow.com/questions/8681', 'https://Stackoverflow.com', 'https://Stackoverflow.com/users/1/']