Twenty Twenty-Five: Rendering issues in Fira Sans font (requires update)

[jonsurrell]

The Fira Sans font included with twentytwentyfive is older and has some issues that are fixed in recent releases. The font does not reserve space for the backtick "`" character, so it overlaps the following character.

Backticks are often used to delimit inline code or a code block and it's especially distracting when they're not positioned correctly or stack so the number of backticks is unclear.

I've tested the latest Fira Sans release and it does not have this issue.

#63963 describes the same issue with twentyfifteen and Noto font.

[jonsurrell]

Backticks issue in the editor

[jonsurrell]

Backticks issue on the frontend

Trac ticket: https://core.trac.wordpress.org/ticket/63964

[lakshyajeet]

Reproduction Report

Description

This report validates whether the issue can be reproduced.

Environment

• WordPress: 6.9-alpha-60093-src
• PHP: 8.2.29
• Server: nginx/1.29.0
• Database: mysqli (Server: 8.4.6 / Client: mysqlnd 8.2.29)
• Browser: Chrome 138.0.0.0
• OS: macOS
• Theme: Twenty Twenty-Five 1.3
• MU Plugins: None activated
• Plugins:

Actual Results

1. ✅ Error condition occurs in both editor and frontend.

Additional Notes

• Triple backticks (```) will be converted to a single backtick character (“`) on the frontend. This is expected behavior.

I was able to reproduce the issue and raised a PR for the same here ​https://github.com/WordPress/wordpress-develop/pull/9886

The PR updates Fira Sans font version for the Twenty Twenty-Five theme style from version 4.203 to version 4.301

Code used to test:

<!-- wp:paragraph -->
<p>Surrounded by: `backticks`. ``` 3 backticks precedes this sentence.</p>
<!-- /wp:paragraph -->

<!-- wp:code -->
<pre class="wp-block-code"><code>Surrounded by: `backticks`. ``` 3 backticks precedes this sentence.</code></pre>
<!-- /wp:code -->

[lakshyajeet]

Before the fix: Editor

[lakshyajeet]

Before the fix: Frontend

[lakshyajeet]

After the fix: Editor

[lakshyajeet]

After the fix: Frontend

[SergeyBiryukov]

In 61267:

Twenty Twenty-Five: Update Fira Sans font for the theme from version 4.203 to 4.301.

This aims to resolve rendering issues with the backtick character.

Follow-up to [59146].

Props lakshyajeet, jonsurrell.
Fixes #63964.