U+229E squared plus draws as a square quartered by a cross, which reads as four panels rather than the two the button makes. U+25EB squared vertical bisecting line is the same picture as the split-down button's squared minus, turned ninety degrees: one square, one line, two panels. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01MPZFnNdHbPGDTqQUNiE4ZN