Feature Proposal: Permalink embedded code widget
### Proposal
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The feature would replace permalinks like:
```
https://gitlab.com/gitlab-org/gitlab/-/blob/9aae0070558f441805453907a176fc926e934d33/LICENSE#L11-16
```
with a code/snippet widget like github:
- https://github.blog/2017-08-15-introducing-embedded-code-snippets/
- https://docs.github.com/en/github/writing-on-github/working-with-advanced-formatting/creating-a-permanent-link-to-a-code-snippet
Current behavior:
https://gitlab.com/gitlab-org/gitlab/-/blob/9aae0070558f441805453907a176fc926e934d33/LICENSE#L11-16
Context: I find it extremely useful to link to specific lines of code when I review merge requests. (Which https://github.com/ben-gibson/GitLink makes really easy).
issue