Unrelated, but this is also a problem in the timeline view and the "Show new" button. Under a slight zoom of 130% the text overflows as the button gets smaller (probably because of the "Go to top button", that doesn't render on my theme) when scrolling.
Column sizes are:
Sidebar: 40 rem
Content: 70 rem
Notifications: 45 rem
Feel free to create another issue, if this one should be kept "Repeat confirmation" only.