If you don’t want Google Chrome to show site handler requests you can disable them easily. Google Chrome lets web services to request you to open some kind of links for instance when you visit Gmail login page in Chrome, it shows a Protocol handler icon on omnibox next to bookmarks icon with a message on hover over “this page wants to install a service handler” -which allows users to set Gmail as default email program in web browser to open all email links.
You should know: some links able to open programs for example mail:to links can open email program and webcal: links add events to Calendar. Here mail:to and webcal: links were called as protocols and Gmail and Google Calendar are referred to as Handlers.
Disabling Service Handler requests in Google chrome
1. From Chrome menu on toolbar select Settings>Show Advanced Settings
2. Under Privacy section click on “Content Settings”
3. When dialog window opens scroll down a bit and in “Handler” section select “Do not allow any site to handle protocols “
4. Click on “Done” button to save the changes.
Tip: You can see all active protocol handlers in Chrome by clicking on “Manage Handlers” button or by visiting chrome://settings/handlers page in browser. This dialog allows to set default handlers or remove already added handlers for protocols.