How to Modify a 3rd-party Chrome Extension

I wanted to add a little feature to the Delicious Chrome extension, but couldn’t find any reference to how to edit/clone a 3rd-party extension. It turns out—at least for making minor mods—it works how you’d think:

  1. Change some extension files.
  2. Restart Chrome.

Caveat: Undoubtedly an update of the extension would wipe out these changes, and following this advice might break the extension (or Chrome!).

Adding a link to the Delicious Bookmarks Extension

On XP, the extension files were in C:\Documents and Settings\<user>\Local Settings\Application Data\Google\Chrome\User Data\Default\Extensions\lnejbeiilmbliffhdepeobjemekgdnok\0.998_0.

To track my work, I did git init; git add . then repeated these steps:

  1. Change file(s)
  2. Restart Chrome
  3. Test. If OK, git commit -m 'desc of changes'

When done I’d added a simple link to the user’s bookmarks (screenshot). I wanted to make this easy for the Delicious team to incorporate these changes, so I generated this patch by diff-ing from the oldest commit:

git diff $(git rev-list HEAD | tail -n 1) > ~/del-chrome.patch