An ImGui auto-resize child reports a too-small height on its first render and
the true height a frame later, so centering on last frame's height made the card
visibly slide for ~2 frames as it converged. Hiding only the very first frame
wasn't enough — the next frame or two still moved.
Track per-dialog height stability: keep the card hidden (laid out + measured, but
clipped) until its measured height holds steady across two frames, then reveal it
already centered. A dialog re-arms on (re)open so each open reveals stable; once
shown it won't re-hide on a mid-dialog content change (just repositions); a
frame cap prevents an ever-changing height from hiding it forever. Fixed-height
dialogs are unaffected. Verified migrate / about / seed-backup / import-key
reveal centered at the settled frame.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
DanS
e6bea8eb04