HTMLblock is a project to let you create custom HTML bloks
Just add <script src="https://htmlblock.vercel.app/block.js"></script> in your document, and start creating!
new HTMLblock(tagName, function).onload()
new HTMLblock("alert","alert").onload()
This example makes that if you put <alert>Hello</alert> in you document, the element will not show, but it will send an alert telling hello.
the .onload() makes that the document runs all the boxes that it can find.