Open the JPG image file you want to convert into an icon. With the plugin, you merely need to save the file with the file extension of .ico to create the icon. Advertisement ...

Icons use the ICO file extension, but due to file formatting issues, it won't work to simply change the file extension of a JPEG file to ICO. Fortunately, ...

By installing Attachment Icons for Gmail, you'll be able to quickly identify if it's a PDF, MP3, ZIP, or any other common file type attached to your e-mail without even having to open it.

Find an extension who's icon you want to change, and swap out the icon_19.png file with the icon you found online. When you restart Chrome, your new icon should show up in its place.