You can filter files in a pull request by file extension type, such as
.js, lack of an extension, code ownership, or dotfiles.
Tip: To simplify your pull request diff view, you can also temporarily hide deleted files or files you have already viewed in the pull request diff from the file filter drop-down menu.
Under your repository name, click Pull requests.
In the list of pull requests, click the pull request you'd like to filter.
On the pull request, click Files changed.
Use the File filter dropdown menu, and select, deselect, or click the desired filters.
Optionally, to clear the filter selection, under the Files changed tab, click Clear filters.