Add Design 3's one-click switch
Clicking anywhere on an account card sets it default (with 1s undo toast). Fastest daily flow; buttons stay for everything else.
Same popup shown in two tab states. Your message cut off at "with…" — if something else was meant to be included, say it in terminal. Your clicks also lingered on Design 3 (one-click switch) — see question at bottom.
Each is a complete rethink — different user flow AND different design language. All GTK3 + CSS (Cinnamon-native, inherits Mint-Y accent). Click the one(s) you like; hesitation clicks are fine.