mermollusc — text → diagram, both ways

drag: move node(s); a single node snaps to alignment
⌥ drag: connect to another node
corner drag: resize
double-click: rename label
↑ ↓ ← →: nudge (⇧ = larger)
⌥ ↑ ↓ ← →: resize selected node (⇧ = larger; in the diagram list it moves instead)
⌘ D: duplicate node(s)
⌘ C / ⌘ V: copy / paste node(s) (flowchart)
S: cycle a node's shape (flowchart), or a selected edge's style (flowchart / block / sequence)
Del: remove node / edge

Tab: the diagram list is in the tab order
↑ ↓ ← →: move between nodes and edges (⇧ = extend selection)
Enter: rename the active item
⌥ ↑ ↓ ← →: move the active node (⇧ = larger; on the canvas the same chord resizes)
c … c: connect nodes: source, then target
d: duplicate the active node
Home / End: jump to the first / last item
g / u: group / ungroup the selection
s: cycle a node's shape, or a selected edge's style
e: collapse / expand a cloud group
F2: focus the action bar for the selection
Del: remove the active item