It's OK for what it does: basic text editors for a page's HTML, CSS, and JavaScript, and a preview window. Each text editor has syntax coloring, autoindent, autocompletion (e.g. enter p tag and it produces closing tag).

But no smart search (the browser's Ctrl+F to seach for e.g. "10" will find line numbers 10, 100, 101, etc.), no search and replace, no keyboard shortcut for run, no ability to edit an existing web page. You can't save to particular locations and file names (a browser limitation).

Useless. It did not work on Firefox

There are two big problems with HTML5 Editor. 1 - no syntax checking, only beauty mode. 2 - problem with suspend mode with my Linux Mint, I cannot awake my desktop. After deleting the add-on from my Firefox-76 my Linux works fine again. So, bye forever!

I like it. But there are two important things I miss: I cannot resize the four areas or remove the space wasting stuff on the left. And I cannot have a spell checker and thus often have typos in my HTML text written I don't notice. So this is okay for playing around with HTML/CSS/JS but the two issues mentioned above unfortunately make it unsuitable for any productive tasks.

Despite the "beginner friendly" description this add-on is quite good. Maybe not too intuitive or too excessively documented but also not really hard to figure out.

This program is amazing. I am moving from html to html 5 and css 3. I can try things in real time! I make a change and click the run button in the upper right hand corner and I know if my change works. I don't know if you can get links to work but I did not get that far yet.

I barely know how to code and go to tutorial sites where the information is free to use. I then modify it to suit my needs. The program can't read my mind but it is handy to test things.

There is a section for java scripts. I don't know what java scripts are but I am going to find out and see if I can get one to run!

I am not trying to be productive. I am learning to create a web site. this application is extremely helpful. It makes the learning and research fun.