In one paragraph
Deprecated HTML tags in use means the source contains one of this check's obsolete elements. Replace it with a suitable maintained structure while preserving information and function. Some old elements still render through compatibility rules; others no longer provide their historical behaviour in mainstream browsers. The finding does not predict a universal removal date or establish that every legacy tag creates the same accessibility problem.
Why it matters
The HTML Standard distinguishes obsolete authoring features from user-agent compatibility behaviour. Browsers can retain parsing and rendering rules for old content while authors are directed not to create new markup with those elements. Obsolete does not mean a scheduled immediate outage.
Presentational wrappers such as font or center can make content styling harder to maintain. Their removal should preserve meaningful emphasis and layout rather than strip all visual distinctions. CSS is appropriate for appearance, while actual emphasis and structure need appropriate semantics.
Functional legacy content needs more than a tag swap. An applet or frameset can represent an old application or navigation model. Identify the intended user task, current alternatives, and real supported environment before retiring it. Replacing scrolling markup with uncontrolled CSS motion is not an accessibility improvement.
How WebAuditOS evaluates this finding
The supplied source-only rule looks for marquee, blink, font, center, frameset, frame, and applet in eligible parsed HTML. A recognised element fails at low severity and is listed by type; absence of those seven passes. Error or unavailable bodies can remain ungraded.
It does not cover every obsolete element, presentational attribute, runtime insertion, or actual visible behaviour. A pass is not a complete HTML validator, a modern-browser certificate, or a full motion and accessibility assessment.
How to fix it
- Locate the actual producer: base template, archived page, rich-text content, third-party embed, or conversion pipeline. A modern outer layout does not clean legacy tags stored inside article bodies.
- Separate meaning from presentation. Replace visual-only font or alignment wrappers with maintained classes, and preserve meaningful emphasis or headings through suitable semantic elements.
- For a simple centred message, an illustration is:
<p class="notice">Read the updated delivery information.</p>
.notice { text-align: center; }This is not a universal replacement for every center wrapper or a demonstration of text contrast and layout conformance.
- Replace obsolete motion with a static equivalent when practical. If movement remains justified, review applicable pause, stop, reduced-motion, and flashing requirements rather than assuming a modern animation API makes it acceptable.
- Review frameset navigation and legacy application features as migration tasks. Preserve useful addressable content and appropriate redirects; do not send unrelated frame documents to one generic homepage automatically.
- Clean stored content with a backup and platform-aware tools. A naive text deletion can remove intended formatting, fallback information, or embedded function. Test on a copy and fix the editor or importer that keeps regenerating the tags.
- Verify responsive presentation, keyboard operation, heading structure, and real task access after replacement. Native or modern markup can still be implemented incorrectly.
- Rescan the limited list and use broader validation or manual review where needed. Judge maintained meaning and functionality rather than a promised ranking improvement.
What the fix can break
Removing wrappers can change selectors, margins, alignment, and inherited colours. Review representative real pages rather than only the smallest isolated example.
Deleting a legacy embed without understanding it can remove useful fallback content or an external workflow. Confirm the actual current function before retirement.
Do not promise that every obsolete tag will stop working soon, or that preserving one necessarily makes the whole site unusable. Prioritise concrete maintenance and user impact.
Questions
Does obsolete mean every browser already ignores the element?
No. Compatibility rendering can persist even when new authoring is discouraged.
Does replacing marquee with CSS automatically solve motion access?
No. Evaluate actual behaviour and applicable controls separately.
Does this rule cover big, strike, and all old attributes?
Not in the supplied seven-element list. Use appropriate broader review for other legacy features.
Which related checks help?
Review conditional comments, doctype, and the website audit checklist.