Skip to main content

1 minute read - Tips

I did not know Firefox could do that: Syntax Error Highlighting in "View Page Source"

Jan 18, 2016

I found a feature I didn’t know about today in Firefox.

The “View Page Source” view, in Firefox, marks in ‘red’ some simple errors.

Rendered HTML

e.g. in the source view below you can see I haven’t added a doctype, and I have a </h2> where an </h1> should be.

View Page Source Shows Errors in Red

This doesn’t catch all malformed HTML you would need an HTML Validator for that.

This feature should be particularly handy given that the inspect element DOM view is the ‘rendered HTML’ not the ’loaded HTML’.

Inspect Element Dom view has ‘fixed’ the error with </h2>


You will need a Github account to comment. Or you can contact me with your comment.

I reserve the right to delete spam comments e.g. if your comment adds no value and its purpose is simply to create a backlink to another site offering training, or courses, etc.