JavaScript answer
ResizeObserver loop limit exceeded
The browser reports this when ResizeObserver callbacks keep causing layout changes before observation delivery can settle.
Common causes
What usually causes this JavaScript error.
Start with the runtime condition that produced the error, then narrow by route, release, browser, and user action.
The callback changes the size of the same element it observes.
A chart, virtual list, or popover measures and writes layout in the same microtask.
A third-party widget triggers resize feedback loops.
The warning is reported as an error even when users do not see a broken page.
Reproduce
How to reproduce the failure.
Write a size-dependent style inside the ResizeObserver callback.
new ResizeObserver(([entry]) => {
entry.target.setAttribute("style", `width: ${entry.contentRect.width + 1}px`);
}).observe(panel);Fix
How to fix it.
Apply the smallest code change that makes the missing, nullable, blocked, or timing-sensitive value explicit.
Move layout writes into requestAnimationFrame
Let the browser finish observation delivery before applying size-dependent writes.
new ResizeObserver(([entry]) => {
const width = Math.round(entry.contentRect.width);
requestAnimationFrame(() => {
entry.target.setAttribute("data-width", String(width));
});
}).observe(panel);Observe a stable wrapper
Observe an outer element and write to a child when visual state needs to change.
new ResizeObserver(([entry]) => {
chart.dataset.width = String(Math.round(entry.contentRect.width));
}).observe(wrapper);Production monitoring
How to prevent and monitor it in production.
Once the local fix is clear, production monitoring should tell you whether the same failure is isolated, user-impacting, or tied to a release.
Track frequency by browser, route, component, and release.
Keep replay attached so teams can confirm whether users saw layout breakage.
Downgrade known benign warnings while preserving alerts for new release spikes.