Clicking OK during the Joint dialog's motion animation was lost about half the time: the preview's busy spinner came and went in the dialog footer between frames, shifting the automatic ids of OK and Cancel, so a click pressed in one frame and released in the next landed on two different ids. The spinner's place is now always taken. Reproduced through the control channel (6 of 14 OK clicks at different animation phases lost before, 0 of 14 after) and covered by a test that presses OK with the preview busy and releases it once idle. The Joints folder is drawn by component_rows for the root, after its folders (as agreed with solvecraft-shell). Co-Authored-By: Claude Opus 5.5 <[email protected]> Claude-Session: https://claude.ai/code/session_01AS5Tn3xieewUSg3uxrMVdL