On the rare occasions that logging out and in doesn't fix it.
Go to the Extension Warehouse in a browser and download the offending plugins and manually install them with the Extension Manager.
If after doing all that they don't update properly in the future there must be some clash with your Internet connection.

Also by the looks of your Frame Buffer it's zoomed in 800% which is why its so blurry. If you click on your Frame Buffer window and use the scroll wheel to zoom back out to 100% is it still blurry?