This Isn't Supposed to Happen: Troubleshooting the Impossible

I recently revamped my portfolio (johnrhea.com). After endless hours of troubleshooting and resolving minor issues on my local machine, I uploaded my newly polished portfolio to the server — only to watch it fail spectacularly.

Isn't it true that browsers parse and execute JavaScript in a similar manner? Sure, Chrome might handle things slightly differently than Firefox, but if the same code resides on two different servers, it should behave identically in either browser, regardless of the server, shouldn't it? Shouldn't it?

Initially, the dynamically generated stars refused to appear, and attempting to engage the game mode resulted in a blank screen. No menacing website foes materialized, nor did they launch any "bad experience" missiles at you — at least, not within the game mode. However, my glitchy website certainly launched a "bad experience" missile at you. Over on the page showcasing my work, miniature cars were supposed to race down the street, yet they too were absent.

I want to assure you, there were absolutely no tears or crying of any sort. I remained incredibly strong and absolutely thrilled — just thrilled — to tackle the challenge of uncovering what was amiss. I frantically searched Google with queries like "What could cause JavaScript to behave differently on two servers?", "Why would a server alter JavaScript functionality?", and "Why does everyone assume I'm crying when I'm clearly not?" But to no avail.

The console displayed errors, but they were nonsensical. I had an SVG element I named "car". I crafted it using vanilla JavaScript, added it to the page, and sent it zooming down a gray strip meant to represent a street. (It's a space-themed setup where you can explore planets. It's genuinely cool. I promise.) I was applying transforms to the car using car.style.transform, but it resulted in an error because car.style was undefined.

I returned to my laptop and checked the code. It ran perfectly without any errors.

To bypass the initial error, I switched from car.style to using setAttribute, such as car.setAttribute('style', 'transform: translate(100px, 200px)');. This merely led me to the next error. The car element was failing on certain data-* attributes I used to store information about the car, like car.dataset.xspeed, which also returned undefined when accessed. This feature has been supported in SVG elements since 2015, yet it wasn't functioning on the server, while it worked seamlessly locally. What in the world could be going on? (Yes, I'm referencing the 1990s band Hoobastank, and no, they have nothing to do with the issue. I simply enjoy... errr... mentioning their name.)

With search engines offering little assistance (mainly because the problem shouldn't even exist), I reached out to my hosting provider, suspecting a server configuration issue might be at play. The courteous tech support tried to assist by checking for server errors and other basic misconfigurations, but found nothing amiss. After reluctantly acting as my coding therapist and listening to my (tear-free) lamentations about embarking on a career in web development, he essentially said they support JavaScript but can't delve into custom code, so good luck. Well, thanks for nothing, person whom I'll call Truckson! (That's not his real name, but I thought "Carson" was too obvious.)

Next, and still tearless, I attempted to explain my issues to ChatGPT with the initial prompt: "Why would JavaScript on two different web servers act differently?" It provided several responses, but they were all incorrect.

• Perhaps there was an issue with inline SVG versus SVG in an img tag? That wasn't the problem.
• Could the browser be interpreting the page as plain text instead of HTML due to some misconfiguration? No, the HTML was being fetched correctly, and the headers were fine.
• Maybe the browser was in quirks mode? It wasn't.
• Could the SVG element have been created incorrectly? You can't create an SVG element in HTML using document.createElement('svg') because SVG uses a different namespace. You need to use document.createElementNS("https://www.php.cn/link/06b44f22bf01b4bad31391ffe00009c4", 'svg'); since SVG and HTML standards, though similar, are quite different. Nope, I had used the createElementNS function with the correct namespace.

Sidenote: During the chat session, ChatGPT started several replies with phrases like, "Ah, now we’re getting spicy ?" and "Ah, this is a juicy one. ?" (emojis included). It also used the term "bulletproof" a few times in what felt like a tech-bro manner. There was also a "BOOM. ? That’s the smoking gun right there" and an "Ahhh okay, sounds like there’s still a small gremlin in the works." I'm torn on whether I find this awesome, annoying, horrible, or scary. Perhaps it's all four?

In desperation, I provided our future robot overlord with some of my code to give it context and demonstrate that none of these were the issue. It continued to focus on misconfiguration and had me output checks to see if the car element was indeed an SVG element. Locally, it was an SVG element, but on the server, it wasn't recognized as such.

• Could using innerHTML to add SVG elements to the car element have corrupted it, causing it not to be recognized as an SVG element? ChatGPT offered to rewrite a portion of the code to fix this. I implemented the new code locally, and it worked! But when I uploaded it to the server... no luck. The same error persisted.

I wept openly. I mean... I managed my emotions in a completely healthy and very masculine manner. And that's where the article would end, without redemption, solution, or answer. Just a broken website and the loud sobs of a man who doesn't cry... ever...

...You're still here?

Alright, you're right. I wouldn't leave you hanging like that. After my non-existent sob session, I vented to ChatGPT, which suggested more console logs, including having the car element print out its namespace. That's when the answer hit me. The namespace for an SVG should be:

<code>https://www.php.cn/link/06b44f22bf01b4bad31391ffe00009c4</code>

But what it actually printed was:

<code>https://www.w3.org/2000/svg</code>

One letter. That's the difference.

Normally, you'd want everything to be secure, but that's not how namespaces operate. And while the difference between these two strings is minimal, it might as well have been document.createElementNS("Gimme-them-SVGzers", "svg");. Hey, W3C, can I join the namespace committee?

But why was it different? You'd be furious if you read this far and it was just a typo in my code, right?

You've invested time in this article, and I've already pulled the fake-out of having no answer. A code typo would probably lead to riots and a flood of bad reviews.

Rest assured, the namespace was correct in my code, so where did that extra "s" come from?

I recalled activating a feature in my host's optimization plugin: automatically fix insecure pages. It scans and converts insecure links to secure ones. In most cases, it's the right move. But apparently, it also changes namespace URLs in JavaScript code.

I disabled that feature, and suddenly, I was traversing the galaxy, exploring planets with cars zooming down gray pseudo-elements, and firing lasers at really terrible websites instead of having a really terrible website. There were no tears (joyful or otherwise) nor any celebratory and wildly embarrassing dance moves that followed.

Have you experienced a similar crazy troubleshooting issue? Have you solved an impossible problem? Let me know in the comments.

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