The thumbnails for Google Chrome are a great feature. It’s like Safari’s Top Sites feature – the difference being a cleaner design.
However the auto-generated thumbnails are not updated often enough for me, or in some cases, are made at the wrong time (for example, when a page is slow or not properly loading). You can force an update however.The sites listed can be easily changed by hovering over one and then selecting the pin or X depending on whether you want to keep or remove that site. But there is no interface for updating the thumbnail images of the site. Safari’s similar Top Sites feature updates the thumbnails ever time the thumbnails are displayed (even if it takes a few moments to load the new thumbnail).
In Chrome, I’ve been seeing the woman’s face for Appleinsider (second thumbnail on the left of the lower row) for months. She’s giving me regular nightmares with her Stepford Wives’s blank stare. I need to fix this.
There is no way to update the thumbnails from within Chrome itself. But it’s pretty straight-forward to remove the current thumbnails thus forcing the application to make new ones.
Open the Default user folder for Chrome’s support files. It can be found at ~/Library/Application Support/Google/Chrome/Default (Said the long way: in your Home folder open the folder titled Library, inside there open the folder titled Application Support, inside there open the folder titled Google, inside there open the folder titled Chrome, inside there open the folder titled Default).
This folder contains all your personal information for Chrome (Preferences, History, Bookmarks, Cookies, Tabs, offline databases and more). The file titled Thumbnails is the one we’re looking for. Don’t be suprised if it’s a big file. It contains every thumbnail Chrome has ever used.
Delete this file. Don’t worry, nothing will happen right away.
Chrome will still be hanging on to those old thumbnails. Quit Chrome to have it let go of them. When it restarts your new tab will be blank for a few moments while it clues in on what has happened (cue evil laughter: Mu-ah-ha-ha-ha!).
When your “Most visited” sites are listed again you will see they use the default thumbnail of a broken camera. When you next visit those sites, new thumbnails will be generated (Woohoo! the scary woman’s stare is gone!)