Whenever you try to install an extension in Chrome from Web store a dialog pops up showing ‘it can access your data on all websites’. By installing that extension you’re allowing that extension do that thing. User must know what permissions installed extensions get. For this, visit chrome://extensions and click on ‘permissions’ link for an extension you’re interested in. ‘Current permissions’ that extension have will be displayed.
What Permissions granted to extensions in Chrome
If you’re interested to know all permissions given for installed extensions in Chrome browser at once you can by installing REM:extension manger extension.
This extension not only displays permissions with details on a popup – which appears when you click on its icon on toolbar- but allows to disable any extension and lets you deny specific permission also which Chrome://extensions page doesn’t offers.
And you should know: Chrome automatically disables extensions if it needs new permissions and prompts you to re-enable it after reviewing them.