code: function disposeInactiveEntries(
    devMiddleware,
    entries,
    lastAccessPages,
    maxInactiveAge
  ) {
    const disposingPages = [];
  
    Object.keys(entries).forEach(page => {
      const { lastActiveTime, status } = entries[page];
  
      // This means this entry is currently building or just added
      // We don't need to dispose those entries.
      if (status !== BUILT) return;
  
      // We should not build the last accessed page even we didn't get any pings
      // Sometimes, it's possible our XHR ping to wait before completing other requests.
      // In that case, we should not dispose the current viewing page
      if (lastAccessPages[0] === page) return;
  
      if (Date.now() - lastActiveTime > maxInactiveAge) {
        disposingPages.push(page);
      }
    });
  
    if (disposingPages.length > 0) {
      disposingPages.forEach(page => {
        delete entries[page];
      });
      console.log(`> Disposing inactive page(s): ${disposingPages.join(', ')}`);
      devMiddleware.invalidate();
    }
  }
docs: dispose inactive pages