#23734 didn't add popups(tippy) to ref issues for the preview tab when adding/editing a file The location of the preview tab: <img width="1214" alt="截屏2023-04-10 13 55 38" src="https://user-images.githubusercontent.com/17645053/230836213-a73f0cee-378c-4a21-93db-583ba2c72f77.png"> This PR resues the logic in `ComboMarkdownEditor.js` to also add popup to hashed comments/pull requests/issues in file editing/adding preview tab. After - On hover: <img width="1222" alt="截屏2023-04-10 13 55 42" src="https://user-images.githubusercontent.com/17645053/230836250-527ca7d0-6ec4-4c68-89ab-4f1b57b09239.png"> --------- Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com> Co-authored-by: silverwind <me@silverwind.io>
