LinkedIn Exfiltrates Data from the Browser
LinkedIn will scan your local browser files in an attempt to identify a number of different browser extensions you may have installed. After inspecting a few of the extension IDs in the resources I began to suspect LinkedIn was attempting to determine if I had certain extensions installed by executing local web requests to the browser itself. LinkedIn abuses this fact and sprays web requests to your local browser in attempt to find extensions.
Source: prophitt.me