HTML Elements & Attributes — exercises and bug fixes

Add a link with the text "Open documentation" pointing to https://developer.mozilla.org that opens in a new tab. Because it opens a new tab, protect the original page with rel="noopener noreferrer".

• Open the link in a new tab.
• Add rel="noopener noreferrer" for security.

Add a horizontal rule to separate two sections, and use a line break inside the second paragraph to put an address on its own line.

• Add an <hr> between the sections.
• Add a <br> inside the address paragraph.

Add a "Submit" button that is disabled until the form is valid — give it the disabled attribute.

Give the abbreviation "HTML" a title attribute containing "HyperText Markup Language" so hovering shows the full term.

Build a submit button with three attributes: type="submit", id="submit-btn", and class="btn-primary".

• Set type="submit".
• Set id="submit-btn".
• Set class="btn-primary".

This link opens in a new tab but is missing rel="noopener noreferrer", leaving the original page exposed. Add it.

This page has no thematic break between the two sections, and the address runs onto one line. Add an <hr> between the paragraphs, and a <br> inside the address to put the city on its own line.

• Add an <hr> between the sections.
• Add a <br> inside the address paragraph.

This button uses disabled="false", but any value — even "false" — still makes a boolean attribute true. Remove the ="false" so the attribute reads as a clean, valueless disabled.

The title attribute on this abbreviation is garbled. Fix it to read exactly "HyperText Markup Language".

This button's id and class values have typos. Fix id to "submit-btn" and class to "btn-primary".

• Fix id to "submit-btn".
• Fix class to "btn-primary".