Use larger programming spaces by scrolling the page

[tiwanari]

This is a note to improve drive.

Problem

I heard that some people want to use more blocks while making programs but the screen is not large enough to do so.

Proposal

I propose to implement a function that allows users to scroll the page and add more blocks.

Note

The position of the trash box is somewhat debatable because we should take care not to move the trash box while scrolling.