We are experiencing major admin-side performance limitations when using large-scale ACF Flexible Content implementations for enterprise page-builder architectures.

After profiling and testing extensively, the bottleneck does not appear to be server-side. The primary issue is browser-side rendering and initialization within the ACF admin UI.

Currently, Flexible Content appears to initialize and render all layouts and nested subfields immediately, even when layouts are collapsed. As the number of layouts and nested fields grows, this causes:

* very large DOM trees

* high browser memory usage

* expensive JS execution

* slow editor interactions

* long admin load/render times

* degraded scalability over time

This becomes particularly problematic for enterprise/editor-heavy implementations where:

* Flexible Content acts as a centralized component/page-builder system

* layouts are intentionally reusable across multiple templates

* editors require access to all layouts within a unified builder

* content teams collaborate across many departments

* websites evolve continuously over multiple years

* new layouts/components are added regularly

In these scenarios, splitting layouts across multiple templates is often not a practical architectural solution.

We believe ACF would greatly benefit from performance-focused rendering improvements for Flexible Content, such as:

* lazy loading flexible layouts

* rendering layouts only when expanded

* virtualized rendering / virtual scrolling

* partial DOM rendering

* deferred field initialization

* async or chunked hydration

* pagination/incremental loading similar to Repeater pagination

* mount/unmount lifecycle handling for collapsed layouts

* background field initialization

* deferred React rendering strategies

Even partial-loading approaches would significantly improve scalability and long-term maintainability for large ACF implementations.

At the moment, all layouts appear to initialize immediately, which creates substantial performance overhead once projects reach enterprise scale.

This feature would greatly improve ACF’s suitability for large-scale page builders, enterprise editorial systems, and long-term evolving websites.