Grimstone Layout Planner
Grimstone is a great little game on itch.io Here's a Link: https://dino0040.itch.io/grimstone
I didn't make it and am not affiliated with the team that did.
This page is a tool designed to help Grimstone players plan out and build better bases, it's intended to go on a second monitor while you play Grimstone.
itch.io embeds games in an iframe that disables copy/paste to clipboard and saving maps as cookies.
To access those features you need to view it by this link:
Zoom the UI to suit you with Ctrl-mousewheel.
Feel free to paste your maps in the comments.