Seeing How Browsers React. and Not That Type of React

Adrian Miasik

2019-11-03 (9:05 p.m. EST)

I noticed something in the previous post. I've tested this file on numerous web browsers and each one reacts slightly differently. Let me show you.

First up is Firefox .
This file (`index.html`) works on Firefox. But I noticed that the console did spit out an error:

The character encoding of the HTML document was not declared. The document will render with garbled text in some browser configurations if the document contains characters from outside the US-ASCII range. The character encoding of the page must be declared in the document or in the transfer protocol.

Alright that should be pretty easy to address. I've used Codecademy to learn web dev before, so I do remember that each website needs to adhere to a certain HTML structure. The first HTML element in any document should be...:

Hmm, interesting. You didn't see it but adding `!DOCTYPE html` (Replace the ` with <> respectively) doesn't appear in my versions of Firefox, Chrome, Internet Explorer 11, and also Microsoft Edge. So even just typing out the correct DOCTYPE element in an HTML file is not enough, it does seems to get deleted by the 4 aforementioned browsers. Good to know. Anyways, I digress.

Second up is Google Chrome .
This file works in Chrome. The console spits out no errors or warnings and accepts this page as is. Great!

Third up is Internet Explorer 11 .
This file works in Internet Explorer 11. The console spits out no errors or warnings and accepts this page as is. Also great!

Last up is Microsoft Edge .
This file works in Microsoft Edge but we do get certain console logs. Let's go all 4 of them:

HTML1300: Navigation occurred.
This is a simple information log, I'm going to ignore this one for now.

HTML1527: DOCTYPE expected. Consider adding a valid HTML5 doctype: " ".
Funny enough, this warning gets removed just like in my Firefox comment before.

HTML1502: Unexpected DOCTYPE. Only one DOCTYPE is allowed and it must occur before any elements.
Okay similar error that I will fix in the next post.

HTML1407: Invalid tag name. First character should match [a-zA-Z].
Okay right so it's complaining about `-` being the first character in this file. We are replacing the first line with the DOCTYPE so we should first apply that solution and see how Microsoft Edge reacts. Funny enough, the copy paste of error 3/4 above is now showing 2 HTML1502 logs on this page.

Alright so what have we noticed? Out of my sample size of 4 browsers, all of them were able to view this file just fine. In fact all four browsers auto-generated a proper HTML structure while putting all the text you are reading into one paragraph element. Neat-o! Firefox was able to tell us our file was incorrect and how it could be incorrect in some browsers. Which is really great to see actually! Microsoft Edge was expecting a DOCTYPE but didn't tell us why nor how. It did however provide us a solution to fix it though. Google Chrome and Internet Explorer 11 had no problems with our files. Now I'm not sure if that concerns me or not. Haha.

So, what's the takeaway from all this? Welp, this tells us that most browsers are not the same. For better or for worse each browser will most likely parse each website slightly differently. (I'm not going to get to far into that, but this does become a headache later on)
My next steps are clear. Let's structure this file using HTML. See you in the next update!