# Sovereign Tech Fund investment improves web interoperability via Igalia

> **Key takeaway:** Funding from the Sovereign Tech Fund enabled Igalia to resolve long-standing web platform gaps in MathML, CSS Typed OM, and the Close Watcher API across major browser engines.

**Published:** 2026-10-29T18:03:04.251469+00:00 
**Source:** Igalia Blog 
**Category:** kernel-os 
**Canonical URL:** https://fosswire.org/news/sovereign-tech-fund-investment-improves-web-interoperability.html 

## Summary
Igalia has released a report detailing the technical achievements made possible through a contract with the Sovereign Tech Fund (STF). The investment targeted critical web interoperability gaps that had previously lacked sufficient momentum for browser vendors to prioritize independently.

The work focused on three primary areas: MathML-Core alignment, the implementation of the CSS Typed OM in Firefox, and the completion of the Close Watcher API. These improvements ensure more consistent behavior across Chromium, Firefox, and WebKit, reducing the fragmentation that often plagues web developers.

## Technical improvements in web standards
- **MathML-Core:** Achieved cross-browser support for CSS properties including font-family: math, math-shift, math-depth, scriptlevel, and font-size: math, while adding support for RTL mirroring of characters and glyphs.
- **CSS Typed OM:** Enabled Firefox to ship the CSS Typed Object Model by default, achieving nearly 92% pass rates in Web Platform Tests and contributing code to the shared Rust-based Stylo codebase.
- **Close Watcher API:** Completed the implementation and integration of the Close Watcher API with HTML popover attributes and the <dialog> element, facilitating interoperable behavior in WebKit.
- **Testing and Coverage:** Increased MathML testing by approximately 400 new subtests, resulting in 99% code coverage for Chromium and 91% for Firefox.

## Why it matters
By funding work that addresses 'black hole' interoperability issues, the Sovereign Tech Fund strengthens the stability of the open web. These improvements reduce the maintenance burden for developers who previously had to write browser-specific workarounds for math rendering and UI element interactions.