That's pretty much it. Not entire web pages but a few words up to an entire line of text rendered in such a way as to be illegible. Most frequently, it looks like letters are superimposed with other letters. But also letters can be missing (e.g. baby becomes bab) or even occasionally rendered as what look like superscripts. Oddly, if I move the cursor over the bad text, it changes to what it should be. Or sometimes I have to select the text. Very rarely, nothing fixes it. This started with a system crash recently that required rebuilding a substantial chuck of hardware and a clean reinstall of Windows. A few days ago, I also did a clean reinstall of Firefox but the problem persists.