<!--IssueSummary start--> <details> <summary> Everyone can contribute. [Help move this issue forward](https://handbook.gitlab.com/handbook/marketing/developer-relations/contributor-success/community-contributors-workflows/#contributor-links) while earning points, leveling up and collecting rewards. </summary> - [Close this issue](https://contributors.gitlab.com/manage-issue?action=close&projectId=278964&issueIid=326385) </details> <!--IssueSummary end--> ### Problem to solve When working with markdown (or any type of prose/text in general), the "classic" git-diff (intended for code) is of limited use. ### Proposal With the logic changes introduced in https://gitlab.com/gitlab-org/gitlab/-/issues/16950 and after Gitaly merges support for word-diff, we should add a user control to enable word-diff mode in merge requests.  ### Further info - Word diff parser https://gitlab.com/gitlab-org/gitlab/-/merge_requests/55105 - Gitlab::Diff::Highlight refactor https://gitlab.com/gitlab-org/gitlab/-/issues/323763 - Word-diff Gitaly support https://gitlab.com/gitlab-org/gitaly/-/merge_requests/3086