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Most Speed Dial thumbnails no longer showing
Since 21 installed most of the speed dial thumbnails are now blank, I'd add a screenshot if attachments were permitted. A few still show, but with most being blank speed dial is now hard work, as I have to look at the sites title, which is beneath the blank square, and can't always be seen in full. And folders, once instantly recognisable by the visible thumbnails, are now indistinguishable from each other.
I hope I've managed to explain this problem thoroughly, but it would have been easier if I could upload a screenshot.
See this discussion, as i hope it may help you. Read through it all.