Block inserter doesn't show that some blocks are disabled

[brentswisher]

Problem
At some point in testing, I disabled the "Core Blocks" in the block manager. A few days later when I came back to work on Gutenberg, I opened up a new post and instead of the normal default paragraph I could tab into, there was just a full-width block inserter:

Thinking this was a change I had missed, I searched for a paragraph in the block inserter, but couldn't find one:

It took me longer than I care to publicly admit to realize what was happening and re-enable the core blocks in the block manager. I thought if it happened to me, it could happen to others, and for someone less familiar with Gutenberg could be even more confusing than it was for me.

Proposed Solution
I think it makes sense to add a notice that there are [x] disabled block (similar to the block manager) somewhere to help users know what is happening. either to the bottom of the block inserter or in the block inserter when no matching blocks are found.

Similar to this message:

I wasn't involved in the Block Manager at all so wanted to put this out there and hopefully get some feedback from someone more familiar with it before I worked up a PR.

[kjellr]

That's a good point. I think at the minimum, we could do something like this:

Clicking the button would open up the Block Manager modal directly. If we want to be extra helpful, something like this could be cool:

[talldan]

That seems like a great idea @brentswisher!

[mapk]

I like the first mockup from Kjell's two ideas. Just show the number of blocks disabled with a button to open the block manager. The second mockup feels like it would need more refinements.

Can you implement mockup 1, @brentswisher ?

[brentswisher]

Thanks for @kjellr for the mockups! I agree with @mapk about liking the first version as well. It might be sometime next week before I have time to work on it with the holiday weekend coming up, but I'm on it :)