URL: twitch.tv

Browser / Version: Firefox 55.2.2
Operating System: Windows 10
Tested Another Browser: No

Problem type: Site is not usable
Description: Text selection and caret function broken in Channel Panels
Steps to Reproduce:
Login/Create account on the service if not already done so
Go to your channel page
Enable the toggle to edit panels
Enter text in the description box
Try to navigate between lines or select text

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