20 Jul

Fix Backspace in Google Chrome

I've written about my fight with Google Chrome updates and broken features in the past. This time let's talk about the brain-dead decision to disable Backspace.

This was their rationale for the change:

We have UseCounters showing that 0.04% of page views navigate back via the backspace button and 0.005% of page views are after a form interaction. The latter are often cases where the user loses data. Years of user complaints have been enough that we think it's the right choice to change this given the degree of pain users feel by losing their data and because every platform
has another keyboard combination that navigates back.

So, just because 50 persons out of each 1'000'000 are f*king idiots, all the others have to suffer? Makes no sense to me.

To prove my point, let's look at the simple Google search: "Google Chrome backspace". It gives 238'000+ results. First few results are: "Backspace to go Back - Chrome Web Store", "Go Back With Backspace - Chrome Web Store", "Back to Backspace - Chrome Web Store", "How to restore the backspace key as a keyboard shortcut to go back in ...", "So where's the Chrome flag to RE-ENABLE BACKSPACE going back a...".

Apparently, I'm not the only one who is hurt by this change.

Hidden BackspaceGoesBack feature

When the change was first introduced in Google Chrome, developers also created a hidden feature that you could set and make Backspace work as it used to. To use it, you just need to launch chrome.exe with a command-line like this:

But in commit 0fe1505a this feature was removed as well.

If you enter the commit number in Chromium Find Releases tool, you'll see that in went out in public in v61.0.3116.0. Another check in Chrome Channel Releases tool will tell you that as of this moment the change is already out for both Canary and Dev channels, and will hit Beta and Stable channels in next months:

So, let's fix this issue for good! And by "fixing it" I don't mean some stupid JavaScript-based Chrome extension (which doesn't work when JavaScript is disabled and in hundreds of other cases..), I mean a proper fix in the code.

Patching Google Chrome again

If you've read my previous post, you know the drill. Set the symbol path, load chrome.dll in IDA, get yourself some coffee and wait. Wait a lot. And after 20-30 minutes you'll be able to start working.

This is the commit that's causing our headaches: commit 0fe1505a and the corresponding place in disassembly of Chrome 58:

What a mess!

Luckily for us, compiler decided to emit nice switch table in version v61.0.3153.2:

To make Backspace work as intended, we can simply overwrite 2 entries in jump table.

Mission accomplished! smile

In the next part of this blog series, I'll show you how to make this patch more user friendly and a few ways how to automate the patching (so that you can receive automatic Google Chrome updates, if you wish).

Till next time!
kao.

31 Aug

Let’s say something good about Google Chrome

In my previous post I criticized Google's decision to disable NPAPI plugin technology. I still think it was a bad decision. But today let's talk about a change that should be an improvement for virtually all users.

Chrome will begin pausing many Flash ads by default to improve performance for users. This change is scheduled to start rolling out on September 1, 2015.

Source: https://plus.google.com/+GoogleAds/posts/2PmwKinJ7nj

Say what? Is Google going against ads? cool Well, not really. HTML5 ads are apparently OK. But those obnoxious Flash-based ads will become click-to-play.

The setting in question is located in Settings->Advanced->Content Settings->Plugins:
chrome_plugin_settings
It has been present in Chrome for several months already. So, I'm guessing that Google will be only pushing out some configuration change, or change the default value for new installations. Who knows, as Google is not giving us any details at this point..

Google's ad detection algorithm might need some improvements and there might be some other side-effects but overall I think it's a great change! Good job Google, you made my day better! smile