I noticed resetting database with exact same plugins and theme activated fixes the problem. But I lose all my data.
Does anyone have any idea what’s happening?
Very strange…
I’m running into this error on the Widgets admin page with no plugins activated, using (for example) Twenty Twenty or Twenty Twenty-One. The error occurs when trying to add any block to any widget zone and prevents me from saving the widget settings.
Tried all sorts of things (de/activating plugins, switching themes, clearing my browser cache and cookies) but nothing seems to get rid of the error. There is NO caching going on, except PHP OPcache on the server side.
This is happening on a dev/test website and where I test all kind of themes, plugins and plugin combinations so I really cannot say when exactly this issue started. But again: deactivating all plugins and switching to a default Twenty theme does not fix it.
Very, very strange…
Update: it occurred to me that there might be some residual stuff in the Inactive widgets. However, as long as the error was there, the Inactive Widgets zone appeared empty (I was sure it wasn’t).
So I switched to a theme that does not support the block based widgets and uses the classic widgets interface. In the classic interface there is a button Clear Inactive Widgets…
Then switched back to the block theme and I could edit the widgets again 🙂
