Ctrl+Enter to save when editing comments is not working

Summary

When editing a comment I can not use Ctrl+Enter to save it, I have to press the "Save comment"-button. This is inconsistent with all other editing boxes where Ctrl+Enter will trigger the default action (Save).

Steps to reproduce

Go to any issue on gitlab.com, edit a comment, press ctrl+enter, nothing happens

What is the current bug behavior?

It doesn't save the comment

What is the expected correct behavior?

It saves the comment

Errata

This is broken for me on both Firefox and Chrome in Linux. Also reported by @MadLittleMods on Chrome in Windows, but works in macOS, see https://gitlab.slack.com/archives/C02PF508L/p1515716312000329