"use strict"; async function doLoadAndGoBack(browser, ext) { let loaded = BrowserTestUtils.browserLoaded(browser); BrowserTestUtils.loadURIString(browser, "https://example.com/"); await ext.awaitMessage("redir-handled"); await loaded; let pageShownPromise = BrowserTestUtils.waitForContentEvent( browser, "pageshow", true ); await SpecialPowers.spawn(browser, [], () => { content.history.back(); }); return pageShownPromise; } add_task(async function test_back() { let extension = ExtensionTestUtils.loadExtension({ manifest: { permissions: ["webRequest", "webRequestBlocking", "https://example.com/"], web_accessible_resources: ["test.html"], }, files: { "test.html": "Test add-on", }, background: () => { let { browser } = this; browser.webRequest.onHeadersReceived.addListener( details => { if (details.statusCode != 200) { return undefined; } browser.test.sendMessage("redir-handled"); return { redirectUrl: browser.runtime.getURL("test.html") }; }, { urls: ["https://example.com/"], types: ["main_frame"], }, ["blocking"] ); }, }); await extension.startup(); await BrowserTestUtils.withNewTab("about:home", async function (browser) { await doLoadAndGoBack(browser, extension); await SpecialPowers.spawn(browser, [], () => { is( content.document.documentURI, "about:home", "Gone back to the right page" ); }); await doLoadAndGoBack(browser, extension); await SpecialPowers.spawn(browser, [], () => { is( content.document.documentURI, "about:home", "Gone back to the right page" ); }); }); await extension.unload(); });