Thanks for the report.
Unfortunately, we currently can’t guarantee support for the Gutenberg plugin as it would require a multitude of checks on top of the ones we currently have to make for all previous WordPress versions.
I’ll take a look as I notice that the navigator isn’t appearing because of errors, but can’t promise anything. I recommend deactivating the Gutenberg plugin in the meantime.
I understand. But if you want to be compatible with future versions of WordPress, it’s good to check compatibility with the Gutenberg plugin. (but probably you already knew)
Yesterday I read they will merge the Gutenberg plugin with version 6.2 of WordPress in 2023.
I’ll be moving this out of bugs as it only is applicable if the Gutenberg plugin is installed, which contains various experimental/new functions that sometime override current functions.
As said above:
On the other hand, it’s important to note that we do plan ahead when there are new WordPress releases planned and make sure to be ready (if any changes are necessary) when the update is available publicly.