Changing min, max or default of a property rebuilt the slider rows of the shader preview, but the rows stayed at 0 x 0. Only the labels were visible until the preview was resized by hand. - Widget.resize only lays out when the size changes. The row count stays the same on such an edit, so the row stack kept its height and never laid out its new children. - syncParams now relayouts the row stack itself after the column around it. Tests: - e2e 28n: a new max rebuilds the slider at 136 x 24, a click at its right end sets level 2. Red against the old build (w 0, h 0). - GM_STEPS=28,31 fresh: ALL PASSED, 106 checks (was 105) - ./check.sh: 132 files, 1952 tests, exit 0 - Check sum 1210 in README, computed (1209 + 1), CI measures it. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>