DLP uploads to you.com not detected consistently

Products

• Data Loss Prevention Network Monitor and Prevent for Email and Web

Issue/Introduction

When uploading files to you.com not all files are detected. 

Cause

Via f12 developer tools you can observe that you.com appears to upload files via text encoding when the files are below some size threashold. 
 "text": "{\"filename\":\"processed_<temp file name>.docx.txt.enc\",\"user_filename\":\"<actual file name>.docx\"

Resolution

Missed detections such as this can be a limitation of the extension method for detecting web uploads. 
For more comprehensive browser coverage, consider 
Monitoring Browsers Using Content Analysis Connectors on Windows Endpoints