Create new branch from the Issue

This is not possible directly from the issue interface. I can try to provide you some workarounds and maybe start a debate why one would want this feature:

Creating branches directly on the web interface

After you've noticed that you need to start working on an issue you can just go to the repository main page (keyboard shortcut gc) and create a branch with the name you want:

Chrome extensions

If this is a must for you, you can create a chrome extension that augments the UI and creates a branch directly from the Issues WebUI using the GitHub API. There's a lot of open source extensions that augment the default WebUI.

Is it the most efficient way to start a new feature?

I think this changes from developer to developer, but having worked with GitHub for 7 years using Issues I've never felt the need for this feature because unless it's a one line change that doesn't require local testing or compilation, I still want to get down to my command line and IDE. If I have to do that, I still have to at least git fetch to get the branch I just created directly through the issue interface. If that's the case I've always preferred to just look at the issue and run git checkout -b branch-name, optionally with git push if my team needs to see the branch.

Then the issue name wouldn't normally translate to a branch name, at least I wouldn't want that. So that option to create a branch from an issue would probably need to spin out a prompt to allow me to name the branch what I wanted.

This is just my personal opinion and nothing else, hope it helps :)

GitHub finally added this feature request to their roadmap.

Summary

The branch is the first thing a developer creates when the start working on a new issue. Creating that association makes it really easy for someone to then follow the work happening and keep everything connected as they take their idea to code.

Intended Outcome

We want to help developers get started on work faster and signal to their team where to find the code changes related to an issue. It should also be really easy to then follow development to the pull request without the user needing to do additional work to link everything together.

How will it work?

From the issue page, a user can quickly create a branch with an auto-generated or custom name that becomes associated with the issue. They can then fetch the branch and switch to it in their development environment and further development changes (such as commits and pull requests) are automatically associated with the issue.

https://github.com/isaacs/github/issues/1125

Nope. You can subscribe this issue.

You could accomplish this by creating a small script.

I'd start by leveraging the Issues Event webhook. This will fire a JSON payload every time an issue is opened. When the webhook fires, your script can then create a new branch using the Create a Reference API endpoint. Note: URL must be formatted as heads/branch, not just branch.

Recently I saw that Github finally added this feature to its Issues Panel. All you have to do is navigate to an Issue on Github and scroll down to the following section:

There is an app that automatically creates branches for issues. You can install it here for free: https://github.com/marketplace/actions/create-issue-branch

If you want to create the branches manually instead of automatically: It does not enable you (directly) to click on create branch from the issue. Instead you would have to write a comment in the issue consisting of: /cib. If you do that, it automatically creates the branch from the issue.

Please note I have no affiliation with the app.