I am writing to report critical issues affecting the functionality and rendering of the [Template Name] template (and associated SP Page Builder) on my Joomla 5.2.3 site. Despite following best practices (PHP 8.3, LiteSpeed, and modern optimization tools), the template generates numerous CSS/HTML validation errors, causing broken layouts in Firefox/Safari and performance degradation. Below is a detailed technical summary for resolution:

Template: Fusion https://www.joomshaper.com/downloads/template/fusion

1. Major Issues Identified A) CSS Validation Errors Obsolete Vendor Prefixes:

-moz-transition, -ms-viewport, -moz-osx-font-smoothing, and other deprecated prefixes are still used in sppagebuilder.css, template.css, and bootstrap.min.css. These are unsupported in modern browsers and trigger console warnings.

Example: -moz-transition: all 0.3s; / Replace with standard 'transition' /

Invalid Syntax:

Typos like background-color; (with a semicolon) and invalid values like border-color: #0037DDpx; (incorrect px suffix).

Example Fix: background-color: #0037DD;
border-color: #0037DD;

Unrecognized Properties:

Deprecated properties like speak: none; (in style.css and joomla-fontawesome.min.css).

B) HTML Validation Errors Duplicate IDs:

Repeated IDs like id="a" (linearGradient), id="offcanvas-toggler", and id="nav-menu" break ARIA compliance and DOM integrity.

Invalid Element Placement:

<style> tags nested inside <div> elements (non-standard placement, blocked by browsers).

Example: <div>
<style>/ CSS here /</style> <!-- Invalid -->
</div>

Malformed Attributes:

height='56px' on <img> tags (should be unitless: height="56").

Incorrect role values (e.g., role="HELIX_ULTIMATE_AIRA_NAVIGATION").

C) Bootstrap Compatibility Issues Outdated Selectors:

Use of deprecated Bootstrap 3/4 syntax like :-moz-placeholder-shown (no longer valid in Bootstrap 5).

D) Google Fonts Loading Errors Spaces in URL Parameters:

Broken font links due to unescaped spaces (e.g., family=Ubuntu Mono → should be family=Ubuntu+Mono).

2. Impact on the Site Cross-Browser Rendering Issues:

Layouts break in Firefox/Safari due to CSS errors (Chrome ignores some non-critical errors).

Console warnings block JS/CSS execution, causing elements like menus, buttons, and animations to fail.

Performance Overhead:

Redundant prefixed properties increase CSS file size, delaying page loads.

SEO and Accessibility Risks:

Duplicate IDs and invalid HTML harm SEO rankings and screen reader compatibility.

3. Steps to Reproduce Install the latest version of [Template Name] and SP Page Builder on Joomla 5.

Run the site through the W3C Validator or check browser consoles (Firefox/Safari).

Observe 150+ errors in CSS/HTML files (attached for reference).

4. Requested Fixes Template/SP Page Builder Update:

Remove all obsolete vendor prefixes and deprecated CSS properties.

Ensure Bootstrap 5 compatibility (Joomla 5’s requirement).

Fix Google Fonts URL encoding and HTML5 validation errors.

Code Quality Improvements:

Avoid inline <style> tags inside <div> elements.

Use unique IDs and valid ARIA roles.

Documentation:

Provide guidance on migrating from legacy code to modern standards.

5. Additional Notes Current Setup:

Joomla 5.2.3 | PHP 8.3 | LiteSpeed | MySQL 8.0.37

Affected Files: sppagebuilder.css, template.css, bootstrap.min.css, and multiple template overrides.

Temporary Workaround:

Switching to Joomla’s default template (Cassiopeia) resolves all errors, confirming the issue is template-related.

Urgency: High. These issues severely impact site usability and professionalism. As a paying customer, I expect a resolution within the next 7 business days or a timeline for an updated template version.

Please acknowledge receipt and provide an action plan.