Tails 2.7 won't start in Virtual Box

Tails 2.7 won’t start in Virtual Box (5.1.8) on Linux 64-bit host.
Tails 2.6, 2.5, … etc have no problems starting up.
Tails 3.0 alpha starts up correctly too.

All using the iso files downloaded off of site verified by
Firefox download plugin.

Feature Branch: bugfix/11965-virtualbox-5.1.8

Related issues

Related to #11992 (closed)
Related to #11848 (closed)
Related to #12001 (closed)

Original created by @jzakiya on 11965 (Redmine)

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