Simple chrome extension script to do what "The Great Suspender" does

background.js

const SUSPEND_AFTER_MS = 5 * 60 * 1000; // 5 minutes

const tabActivity = new Map();
let lastActiveTabId = null;

chrome.tabs.onActivated.addListener(activeInfo => {
  if (lastActiveTabId !== null) {
    // Reset the last active tab's activity time
    tabActivity.set(lastActiveTabId, Date.now());
  }
  // Update the last active tab ID
  lastActiveTabId = activeInfo.tabId;
});

setInterval(() => {
  chrome.tabs.query({}, tabs => {
    const now = Date.now();
    for (const tab of tabs) {
      const isEligible =
        !tab.active 
        && !tab.pinned 
        && !tab.discarded
        && tab.status !== "unloaded"
        && tab.url.startsWith("http") 

      if (isEligible) {
        if (!tabActivity.has(tab.id)) {
          tabActivity.set(tab.id, now);
          continue;
        }
        if (tabActivity.get(tab.id) == null) {
          // This tab has been suspended already
          continue;
        }

        const lastActive = tabActivity.get(tab.id);
        if (now - lastActive > SUSPEND_AFTER_MS) {
          chrome.tabs.discard(tab.id);
          tabActivity.set(tab.id, null); // Mark as suspended
        }
      }
    }
  });
}, 60 * 1000); // Check every minute