While the developer may be well-intentioned, there's still a great amount of risk you are taking in using this or any other extension, because they can be easily updated to a new version without you ever being notified about it.

Learned my lesson after having to deal with a Bitcoin Ticker that was automatically replacing the withdrawal addresses in various exchanges to the ones pointed out in the extension. I was on the verge of losing everything.

If you want to use it, at least install this:

Extensions Update Notifier
https://chrome.google.com/webstore/detail/extensions-update-notifie/nlldbplhbaopldicmcoogopmkonpebjm?hl=en

or

Install the Chrome extension source viewer from the Chrome webstore
https://chrome.google.com/webstore/detail/chrome-extension-source-v/jifpbeccnghkjeaalbbjmodiffmgedin/related

1 - Download a specific version of a Chrome extension.

2 - Go to your extensions folder in Chrome, turn on Developer Mode, and click on the options link below Chrome extension source viewer

3 - Open the viewer

4 - Open the recently downloaded "insertname" file

5 - Click "Download" in the upper left corner. Finder will open showing you a null folder that contains the "insertname" logo, a javascript file, and the manifest.

6 - Open the Manifest JSON file (Any text editor will do)

7 - Change the update url (found in quotations) to http://127.0.0.1 (you own local machine IP) and save the file

8 - Optional: Go to the Chrome Developer tools and choose to pack a chrome extension to create a .crx file again.

9 - Drag the entire null folder or the .crx file (with the newly edited manifest file) into your Chrome Extensions page with developer mode turned on.