i was inspect with my page and i get this warning...
Deferred long-running timer task(s) to improve scrolling smoothness. See crbug.com/574343
Blink deferred a task in order to make scrolling smoother. Your timer tasks should take less than 50ms to run to avoid this. Please see https://developers.google.com/web/tools/chrome-devtools/profile/evaluate-performance/rail and https://crbug.com/574343#c40 for more information.
This occurs when Blink (Chrome's rendering engine) decides to delay executing a timer (like a function passed to
setInterval) because those functions are generally taking >50ms to execute and there is user touch input. It's done to prioritize handling user input (like scrolls and taps) above what the site is doing.
If you've encountered this message, then its likely your users will get similar behavior. Here's how to reproduce this scenario:
The method for how to solve this is directly from the referenced issue in the console message down in comment 40:
You want these functions to execute faster or less frequently.