Did you know you can enable Bugzilla integration on your project?
Take a look at 'Project Settings' > 'Integrations'. AFAIK It will display the "Issues" link but will redirect you to bugzilla, and some other UI integrations.
We already have an integration feature with Bugzilla using git hooks and some keyword in the commit message.
This feature looks interesting, but this feature is sadly only available in enterprise edition.
This is my problem currently with the move from Phabricator to Gitlab, we are losing tons of features: review approval, meta project (documentation, visual design group, promo, website, ...), mockups, meta tasks and more. And those features exist but only in the enterprise edition, that is not open source.
Take a look at 'Project Settings' > 'Integrations'. AFAIK It will display the "Issues" link but will redirect you to bugzilla, and some other UI integrations.