An editor for plain text where you can also seamlessly insert line drawings

clean up Drawing.before after creating undo event

This isn't a bug here, but it led to a bug in lines 2.

Created by  akkartik  on August 31, 2024
237LRHDOEGASSOTFLGWEZPD5PRY2NGZXCIGWCNDJWIWH4BKSOBZQC
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