'''''ClearType Issue''''' If you adjust the zoom one tick -- hold down the Ctrl key and tap either the + or - key -- does the missing content fill in? Your symptoms plus a successful zoom test are characteristic of a new bug in Firefox 59-60 affecting users who disabled '''ClearType font smoothing''' in their Windows settings. This is expected to be fixed in a 59.0.2 update, but it's not clear when that will be released. If you don't want to re-enable ClearType, then the workaround is to temporarily ''disable'' Firefox from using hardware acceleration. The following article has the steps for that, and the change takes effect the next time you exit Firefox and start it up again: [[Firefox's performance settings]] <img src="https://prod-cdn.sumo.mozilla.net/uploads/images/2018-03-20-09-16-11-31f681.png"> Any improvement?