Dominik Schwind

Not really ??
That was just a reply to your comment that you looked at the code.

Also there is no shortcode – it’s a sidebar widget, which is something different. So I guess I am limiting this to people who remember the old ways of customizing WordPress sites, which is probably fewer and fewer people every day.

I’m glad you found something that works for you!

That’s a bit harsh. The code is pretty simple, so it shouldn’t be too hard to figure out what it does and how it does it.

It still works fine for me – it does need a theme that supports the old sidebar widget system, though. Most newer themes use the Gutenberg/block based widgets.

We have the same error and this page was the first result in Google, so I thought I’ll share my findings, maybe it helps someone. (Didn’t help me so far, but who knows.)
A bare WordPress 6.1 or newer doesn’t have the problem with PHP 7.4, 8.0, 8.1 or 8.2. That’s because they only check the differences in title, content and excerpt which are all strings. Some plugins or themes might hook into _wp_post_revision_fields and add fields that are arrays. The “type safety” in the function wp_get_revision_ui_diff doesn’t account for this and that’s when everything breaks.

Hi, we’re not actively developing this plugin anymore, so hints like this for people who still use it are super helpful, thank you very much!

Okay, that sounds like a JavaScript problem. We tried to make it work with as many themes and other plugins as possible but it can’t be helped that there might be some incompatibilities.

That problem sometimes happens when the theme’s CSS and the plugin’s CSS clash. We try to make it work with as many themes as possible but there’s always a chance some rules overwrite each other.

Is your server in the same timezone as you are?

Thanks. ?? I think to be more precise your code is calling current_user_can() which in turn calls wp_get_current_user()

We’re including the theme’s main CSS file. Some themes might not have all their style rules in there and any CSS that has been added through the WordPress backend isn’t included, either.

It’s under “Tools”

Yes, on the 5th the links for 1, 2, 3, 4 and 5 will be clickable.

When you open the page with the calendar-shortcode and click “Preview” all the calendar numbers should be clickable.

Open the page with the calendar from the WordPress admin backend and click on “Preview”

Oh, okay.
I’ll have a look at that. Neither of us is using that plugin so it didn’t come up in testing.
Thanks for hunting down that bug!

At the moment that’s not possible, no.
I actually don’t know why and it’s pretty surprising that nobody asked before. I’ll put it on my list for next year.