Created attachment 460443 [details] A short video demoing the bug Overview Hello, I'm a contributor to Jenkins CI. We're facing an issue solely on Safari/WebKit where text will occasionally jitter and resize when hovering/interacting with an element, e.g. a link in the sidebar. This can be hard to reproduce sometimes but I've had success with the steps below repeatedly. This behaviour is limited to Webkit/Safari and I can't reproduce it in other browsers. Steps to reproduce Open a private Safari window Navigate to https://weekly.ci.jenkins.io Hover over elements in the sidebar and watch as they jitter/change size Expected results The text should stay the same size when hovering/interacting with an element. Additional information We use REM for font sizes, e.g. a link in the sidebar might have the font-size set to 0.9rem. This has occurred for as long as I can remember using Safari/Jenkins.