Disappearing categories

Houston TX

Description

Recently when signing into Craigslist, I found a strange happening and haven't been able to figure out why it is happening. See the attached screen shot. You will notice that random categories and listings are totally missing. If I left click on the space where the category is supposed to be, it will appear, let go of the mouse button and it will open the category as normal. Anyone have a clue as to why the disappearing act is happening?