The sidebar on all the Blogger blogs has been very jumpy, lately -- just shaking itself up and down. The main post portion is stable. It is happening to me on more than one computer, too. Then I went to a couple of Wordpress blogs and there is no problem there with the sidebars.
Maybe this is what is happening as Google tries migrating Blogger to mobile views (which usually don't include the sidebar -- just the posts).
I know I have astigmatism, but didn't know I have nystagmus as well!