This version adds support for Java 1.17 and Bedrock 1.17 worlds.
This is still experimental so create backups before using.
It supports variable height worlds that can be created in Java 1.17 using data packs.
The floor tiles now appear at the bottom of the editable area and a ceiling tile has been added at the world height. This should make it easier to work out what can be edited for any given world now that it is not fixed.