[Violation] Forced reflow while executing JavaScript took 34ms

That message indicates the browser had to pause JavaScript execution to re-compute layout (“reflow”), which took 34 ms. It’s more of a performance warning than an error. It usually appears when scripts frequently read layout properties (like offsetWidth, clientHeight, etc.) shortly after writing to styles, forcing the browser to recalculate layout immediately. If it’s not causing noticeable slowdowns, you can ignore it; otherwise, you may consider minimizing layout thrashing by batching reads and writes or using requestAnimationFrame.