Don't do canvas fingerprinting

Summary

Gitlab seems to read data from canvas, probably for doing fingerprinting, which causes parts of the gitlab UI to fail when users block canvas-reading. Additionally, tracking users with canvas fingerprinting is against privacy.

I cross-post the issue from https://gitlab.com/gitlab-org/frontend/gitlab-ui/issues/18 since it may not be the right bugtracker.

Steps to reproduce

• Start a fresh Firefox profile
• Install canvasblocker extension
• Configure the extension to block canvas reading API
• Open any gitlab MR
• Try to open the changes tab

What is the current bug behavior?

The changes view is blank. The assignee info doesn't load. Etc. Similar problems occur when trying to view a gitlab issue.

What is the expected correct behavior?

The changes of the MR are shown. The assignee info is present.