seen: 2026-10-30, mosaic, todarch cube on a phone. selim: "you should not have this bottom navigation bar in this cube design application. this is a violation too. this is not a cube design menu or navigation structure. we don't have that."
picture: as violation 15 (the bottom of the screen).
breaks: 6 and 25 (zoom is a change of distance; going out is zooming out: a tab bar jumps sideways between levels), and the reasoning of violation 10 (navigation in a corner is chrome, the same on every page and blind to where you are).
why it feels wrong: in a cube every place is reached by going in and out: the faces from afar, a value, a piece, its face. two tabs at the bottom, "cube" and "to-dos", were two doors to two levels of the same cube, always there, so the to-dos were reachable both by zooming and by a jump. that is mosaic's own shell (every sub-app has tabs) laid over a cube design app.
how it follows (built the same evening): the todarch cube keeps one tab, and mosaic draws no bottom nav for a sub-app with one. everything is reached by zooming. mosaic's shell (top bar, app switcher) stays: it is the way between apps, not within this one.
status: fixed, lang-app-fe#105/#106.