Recording seek no longer blocks page; yield budget opt-in

1.408.1

Patch Changes

• #4226 3b02a78 Thanks @ksvat! - The replayer can now yield to the event loop while fast-forwarding to a seek target, via the new opt-in seekYieldBudgetMs player config. Seeking in a long, event-dense recording rebuilds the target frame by re-applying every event since the last full snapshot in one uninterrupted main-thread pass, which can block the page for many seconds and trigger the browser's "Page Unresponsive" dialog; when a yield budget is set, the rebuild runs in time-budgeted chunks instead, and a newer seek cancels any rebuild still in flight so rapid scrubbing only pays for the last seek. A superseded rebuild also resets the machine's lastPlayedEvent so the next seek performs a full rebuild rather than trusting a partially-applied history. The default (0) keeps the previous fully-synchronous behavior. (2026-07-30)