Hi @kleineschritte,
First the widget doesn’t show the title on the page. I didn’t change any settings except disabling all boxes under “Stats Tag settings”.
Yeah, the widget block not displaying a title is my fault. I changed something on the last release (5.3.6) that’s now preventing the block from displaying the title as set by the user. Didn’t notice that until it 5.3.6 was out.
I was planning to release version 5.3.7 right away to fix that but then noticed that WordPress wasn’t styling the widget heading properly as per the sidebar’s configuration (see issue 32723). WordPress 5.8’s new Widgets implementation isn’t fully backwards compatible with how widgets used to work, causing these sort of issues.
The current recommendation of the WordPress team is to manually add a Heading block before the widget (their thinking is that widget blocks shouldn’t have a heading at all because none of the regular blocks have one either) and even then there’s a good chance that the Heading block won’t be styled properly unless you add some specific CSS classes to it as designed by your current theme.
There’s a proposal to bring back some missing features so widget blocks can be styled according to the sidebar’s configuration (see issue 33638) but we’ll have to wait at least until WordPress 5.8.1’s release to use it. If/when that happens I’ll be able to have the widget block display a heading as intended, for the time being the only workaround is -as mentioned earlier- to use a Heading block.
Alternatively, if you don’t want to deal with any of that, you can also install the Classic Widgets plugin to get the old Widgets screen back so you can use the “classic” WordPress Popular Posts widget instead of the block one which will resolve the no heading issue you’re having now.
The second thing is that as soon as I change the last point “Theme” to any other than “none” all the images are displayed as a gray box (not the “no image available”-image). The same thing happened with the old widget which is why I was tinkering with it in the first place. So it could be totally unrelated to this update.
If it was happening before then there’s likely a configuration issue here. Please try following the suggestions from this FAQ and if the issue persists open a new topic and share more details about your website (URL, active plugins, etc) so I can have a look: My popular posts thumbnails are not loading. Why is that?