diff --git a/toolkit/components/thumbnails/BackgroundPageThumbs.jsm b/toolkit/components/thumbnails/BackgroundPageThumbs.jsm
index 45109f5147a..3932afe9761 100644
--- a/toolkit/components/thumbnails/BackgroundPageThumbs.jsm
+++ b/toolkit/components/thumbnails/BackgroundPageThumbs.jsm
@@ -86,30 +86,6 @@ const BackgroundPageThumbs = {
     this._processCaptureQueue();
   },
 
-  observe: function(subject, topic, data) {
-    // oop-frameloader-crashed - see if it was ours?
-    if (this._thumbBrowser) {
-      let frameLoader = subject.QueryInterface(Ci.nsIFrameLoader);
-      if (this._thumbBrowser.messageManager == frameLoader.messageManager) {
-        Cu.reportError("BackgroundThumbnails remote process crashed - recovering");
-        this._destroyBrowser();
-        let curCapture = this._captureQueue.length ? this._captureQueue[0] : null;
-        // we could retry the pending capture, but it's possible the crash
-        // was due directly to it, so trying again might just crash again.
-        // We could keep a flag to indicate if it previously crashed, but
-        // "resetting" the capture requires more work - so for now, we just
-        // discard it.
-        if (curCapture && curCapture.pending) {
-          curCapture._done(null);
-          // _done automatically continues queue processing.
-        }
-        // else: we must have been idle and not currently doing a capture (eg,
-        // maybe a GC or similar crashed) - so there's no need to attempt a
-        // queue restart - the next capture request will set everything up.
-      }
-    }
-  },
-
   /**
    * Checks if an existing thumbnail for the specified URL is either missing
    * or stale, and if so, queues a background request to capture it.  That
@@ -221,18 +197,11 @@ const BackgroundPageThumbs = {
 
     browser.messageManager.loadFrameScript(FRAME_SCRIPT_URL, false);
     this._thumbBrowser = browser;
-    // an observer to notice if the remote process crashes.  There is also an
-    // "ipc:browser-destroyed" sent both for normal and abnormal terminations,
-    // but it's not currently possible to determine what browser it was for
-    // (although nsITabParent is probably going to grow a way of determining
-    // it at some point)
-    Services.obs.addObserver(this, "oop-frameloader-crashed", false);
   },
 
   _destroyBrowser: function () {
     if (!this._thumbBrowser)
       return;
-    Services.obs.removeObserver(this, "oop-frameloader-crashed");
     this._thumbBrowser.remove();
     delete this._thumbBrowser;
   },
@@ -257,8 +226,7 @@ const BackgroundPageThumbs = {
   },
 
   /**
-   * Called when the current capture completes or fails (eg, times out, remote
-   * process crashes.)
+   * Called when the current capture completes or times out.
    */
   _onCaptureOrTimeout: function (capture) {
     // Since timeouts start as an item is being processed, only the first
diff --git a/toolkit/components/thumbnails/test/Makefile.in b/toolkit/components/thumbnails/test/Makefile.in
index 156dcdea1f0..418eeb00754 100644
--- a/toolkit/components/thumbnails/test/Makefile.in
+++ b/toolkit/components/thumbnails/test/Makefile.in
@@ -25,7 +25,6 @@ MOCHITEST_BROWSER_FILES += \
 	browser_thumbnails_background_crash.js \
 	browser_thumbnails_update.js \
 	thumbnails_background.sjs \
-	thumbnails_crash_content_helper.js \
 	thumbnails_update.sjs \
 	$(NULL)
 endif
diff --git a/toolkit/components/thumbnails/test/browser_thumbnails_background_crash.js b/toolkit/components/thumbnails/test/browser_thumbnails_background_crash.js
deleted file mode 100644
index b51551ecf97..00000000000
--- a/toolkit/components/thumbnails/test/browser_thumbnails_background_crash.js
+++ /dev/null
@@ -1,117 +0,0 @@
-/* Any copyright is dedicated to the Public Domain.
- * http://creativecommons.org/publicdomain/zero/1.0/ */
-
-const TEST_PAGE_URL = "http://mochi.test:8888/browser/toolkit/components/thumbnails/test/thumbnails_background.sjs";
-const TEST_CONTENT_HELPER = "chrome://mochitests/content/browser/toolkit/components/thumbnails/test/thumbnails_crash_content_helper.js";
-
-const imports = {};
-Cu.import("resource://gre/modules/BackgroundPageThumbs.jsm", imports);
-Cu.import("resource://gre/modules/PageThumbs.jsm", imports);
-Cu.import("resource://gre/modules/Task.jsm", imports);
-Cu.import("resource://gre/modules/commonjs/sdk/core/promise.js", imports);
-
-function test() {
-  waitForExplicitFinish();
-
-  spawnNextTest();
-}
-
-function spawnNextTest() {
-  if (!tests.length) {
-    finish();
-    return;
-  }
-  let test = tests.shift();
-  info("Running sub-test " + test.name);
-  imports.Task.spawn(test).then(spawnNextTest, function onError(err) {
-    ok(false, err);
-    spawnNextTest();
-  });
-}
-
-let tests = [
-
-  function crashDuringCapture() {
-    // make a good capture first - this ensures we have the <browser>
-    let goodUrl = testPageURL();
-    yield capture(goodUrl);
-    let goodFile = fileForURL(goodUrl);
-    ok(goodFile.exists(), "Thumbnail should be cached after capture: " + goodFile.path);
-    goodFile.remove(false);
-    // inject our content script.
-    let mm = injectContentScript();
-    // queue up 2 captures - the first has a wait, so this is the one that
-    // will die.  The second one should immediately capture after the crash.
-    let waitUrl = testPageURL({ wait: 30000 });
-    let deferred1 = capture(waitUrl);
-    let deferred2 = capture(goodUrl);
-    info("Crashing the thumbnail content process.");
-    mm.sendAsyncMessage("thumbnails-test:crash");
-    yield deferred1;
-    let waitFile = fileForURL(waitUrl);
-    ok(!waitFile.exists(), "Thumbnail should not have been saved due to the crash: " + waitFile.path);
-    yield deferred2;
-    ok(goodFile.exists(), "We should have recovered and completed the 2nd capture after the crash: " + goodFile.path);
-    goodFile.remove(false);
-  },
-
-  function crashWhileIdle() {
-    // make a good capture first - this ensures we have the <browser>
-    let goodUrl = testPageURL();
-    yield capture(goodUrl);
-    let goodFile = fileForURL(goodUrl);
-    ok(goodFile.exists(), "Thumbnail should be cached after capture: " + goodFile.path);
-    goodFile.remove(false);
-    // inject our content script.
-    let mm = injectContentScript();
-    // the observer for the crashing process is basically async, so it's hard
-    // to know when the <browser> has actually seen it.  Easist is to just add
-    // our own observer.
-    let deferred = imports.Promise.defer();
-    Services.obs.addObserver(function crashObserver() {
-      Services.obs.removeObserver(crashObserver, "oop-frameloader-crashed");
-      // spin the event loop to ensure the BPT observer was called.
-      executeSoon(function() {
-        // Now queue another capture and ensure it recovers.
-        capture(goodUrl).then(() => {
-          ok(goodFile.exists(), "We should have recovered and handled new capture requests: " + goodFile.path);
-          goodFile.remove(false);
-          deferred.resolve();
-        });
-      });
-    } , "oop-frameloader-crashed", false);
-
-    // Nothing is pending - crash the process.
-    info("Crashing the thumbnail content process.");
-    mm.sendAsyncMessage("thumbnails-test:crash");
-    yield deferred.promise;
-  },
-];
-
-function injectContentScript() {
-  let thumbnailBrowser = imports.BackgroundPageThumbs._thumbBrowser;
-  let mm = thumbnailBrowser.messageManager;
-  mm.loadFrameScript(TEST_CONTENT_HELPER, false);
-  return mm;
-}
-
-function capture(url, options) {
-  let deferred = imports.Promise.defer();
-  options = options || {};
-  options.onDone = function onDone(capturedURL) {
-    deferred.resolve(capturedURL);
-  };
-  imports.BackgroundPageThumbs.capture(url, options);
-  return deferred.promise;
-}
-
-function fileForURL(url) {
-  let path = imports.PageThumbsStorage.getFilePathForURL(url);
-  let file = Cc["@mozilla.org/file/local;1"].createInstance(Ci.nsIFile);
-  file.initWithPath(path);
-  return file;
-}
-
-function testPageURL(opts) {
-  return TEST_PAGE_URL + "?" + encodeURIComponent(JSON.stringify(opts || {}));
-}
diff --git a/toolkit/components/thumbnails/test/thumbnails_crash_content_helper.js b/toolkit/components/thumbnails/test/thumbnails_crash_content_helper.js
deleted file mode 100644
index 6323f6dfaa4..00000000000
--- a/toolkit/components/thumbnails/test/thumbnails_crash_content_helper.js
+++ /dev/null
@@ -1,29 +0,0 @@
-/* Any copyright is dedicated to the Public Domain.
-* http://creativecommons.org/publicdomain/zero/1.0/ */
-
-// Ideally we would use CrashTestUtils.jsm, but that's only available for
-// xpcshell tests - so we just copy a ctypes crasher from it.
-Cu.import("resource://gre/modules/ctypes.jsm");
-let crash = function() { // this will crash when called.
-  let zero = new ctypes.intptr_t(8);
-  let badptr = ctypes.cast(zero, ctypes.PointerType(ctypes.int32_t));
-  badptr.contents
-};
-
-
-TestHelper = {
-  init: function() {
-    addMessageListener("thumbnails-test:crash", this);
-  },
-
-  receiveMessage: function(msg) {
-    switch (msg.name) {
-      case "thumbnails-test:crash":
-        privateNoteIntentionalCrash();
-        crash();
-      break;
-    }
-  },
-}
-
-TestHelper.init();