Add intellisense / Integrate intelli-octo
Adding intellisense could provide contributors and reviewers with a huge set of tools to better understand the code they're looking at.
Whether that is in the blob editor for code contributions or MR diffs for code review.
Today I stumbled across https://twitter.com/Rygu/status/852495593956159488 which shares https://github.com/pd4d10/intelli-octo. IntelliOcto is a a chrome extension that provides intellisense for github, gitlab and bitbucket. From a brief look it looks like it could be modified and integrated directly into gitlab for everyone to use. It would be enough of a modification to warrant a fork that then continues to be developed separately as its currently in typescript and is a chrome extension.
Currently it only supports TypeScript, JavaScript, CSS, LESS, SCSS and HTML but this is a great start.
It would most likely need to be forked and then be developed internally if we were to use it