Gutenberg: Block SelectControl saves attributes but after a reload of Gutenberg it loads its defaults. Why?

I thought I had it. I added an attribute “max_level” and a SelectControl element “SelectMaxLevel”. Everything works according to plan: I can set the max level and it is saved in the block. When I save the post and display the post see that the php part uses the “maximum level” variable. But when I edit the post the blocks loads it’s default value. Why does this happen?

Question about repurposing WordPress 404 handler

I’ve been experimenting with repurposing WordPress’s 404 handler/template file for a Real Estate site that I’m developing. I understand that when a non-existent URL is requested, the 404 page gets served up and that it returns a 404 status code (instead of a 200). But I’ve recently found a way to adapt the 404 template file so that it does something a bit more creative. More specifically, I’m first parsing the non-existent URL that was requested, and then using the returned value to query an external API and then display the returned data. So far it’s working much better than I’d expected, though I’m aware of one significant issue that I’m hoping I can address.