File browser in change review screen without file name truncation

The file browser in GitLab’s (14.2.1) change review screen does not have a resizable width. Longer file names get truncated. This makes it inconvenient to use, even if the list view option is selected.

With the following CSS-override this can be fixed:

.diff-tree-list.js-diff-tree-list.px-3.pr-md-0 {
width: 500px !important;
}

I hope future releases of GitLab come with a more user-friendly file browser!

Is it possible to apply this css rule across a whole self-managed gitlab instance? Or does each user have to hack this into their browser.