Hacking the macOS Twitter client
Twitter recently dropped support for their macOS client. While there are many fine third-party Twitter clients, there are some things they don’t do as well, due to limitations in Twitter’s public API.
But just because Twitter has abandoned their software, that doesn’t mean it’s dead! In this post, I will walk you through how to make a small change: update the program to support 280-character tweets.
First, of course, you will need the macOS Twitter client!
Second, you will need a disassembler. Here, I’ll be using Hopper, which is my favourite tool for exploring Objective-C programs.
In Hopper, choose File › Read Executable to Disassemble…, navigate to
/Applications/Twitter.app/Contents/MacOS/, and open
Finding the relevant code
Objective-C programs leave a ton of information in the executable, so it’s often enough to make a few educated guesses and search for them. We know the current Tweet character limit is 140 characters, so we could search for limit, maximum, or something like that.
Making the change
Select the line with
mov eax, 0x8c on it, and then use Modify › Assemble Instruction….
Next, select File › Produce new Executable….
Hopper will tell you that this file is a signed application that has been modified, and ask if you’d like to remove the signature.
Choose yes, since the signature is no longer valid.
Make a backup if you want, and then overwrite the old
Trying it out
Launch the modified Twitter app, and try composing a new tweet!