Crumble is a prototype stabilizer circuit editor.
Read the manual

Load example: surface code (d=3,r=2)
Load example: bacon shor code (d=7,r=2)
Load example: three coupler surface code (d=7,r=4)
Load example: surface code Y basis transition round (d=7)

Show Import/Export
Clear All

Clear All Pauli Marks
Clear Selected Marks (space)

Redo (ctrl+Y)
Undo (ctrl+Z)

Next Layer (e)
Prev Layer (q)

Rotate 45 Clockwise ↻ (t)
Rotate 45 Mathwise ↺ (shift+t)

Set Timeline Focus (L)
Clear Timeline Focus