I do not know why, but when the styles are declared as settings of the
BlockEditorProvider, then typing anything is too slow to be usable.
But, when the styles are declared within the BlockEditor, without the
useSelect hook, then it works as expected (not fast, not that, but at
least not intolerably slow.)
I tried with a useMemo to keep the styles the same when there is no
change, which is most of the time, but the behaviour is the same.
Since i do not need to pass the styles from without the application,
at least not for now, my only option is to have them directly in
BlockEditor.
Despite the fact that Gutenberg developers did not care at all about
uses of this library outside WordPress until last year[0], and that it
is almost impossible to do something that goes beyond the very basic
without using “private APIs”, they insist that the isolated block
editor should be “deprecated”[1].
I do not particularly care much about the isolated block editor, as it
_does_ use all these private APIs and, thus, it is very difficult to
use unless you use the exact same dependencies, otherwise it emits a
weird error regarding “unlocking” things that are not “locked” (i.e.,
the new-fangled way of “protecting” private APIs[2]). And,
apparently, things got easier with Gutenberg 18.5 with the
introduction of the BlockCanvas.
However, it is still a very frustrating experience, and the
documentation for most components and packages is next to
non-existent.
Nevertheless, i managed to get a barely functional editor that still
has some missing features, like the color of rich texts’ highlight
format[3], but it i believe it is a good base to grow the custom
editor on top of.
[0]: https://github.com/WordPress/gutenberg/issues/53874
[1]: https://github.com/WordPress/gutenberg/issues/57672#issuecomment-1883119040
[2]: https://developer.wordpress.org/block-editor/reference-guides/packages/packages-private-apis/
[3]: https://github.com/WordPress/gutenberg/issues/55036
jordi fita mas