[Bug]: Visual lag when dragging a node fast — node jumps to catch up with cursor

[Kalliser]

Affected Version

18.6.1

Reproduction URL (StackBlitz, GitHub, etc.)

No response

Steps to Reproduce

Summary

When the user clicks on a draggable node and immediately moves the cursor very fast (within ~1 frame), the node visually lags behind by 20–50px and then snaps to catch up with the cursor on the next pointer move. The faster the initial flick, the bigger the visible jump.

Reproduction

Set up any basic with a single [fNode] node + fDragHandle on its header.
Mouse down on the header.
Move the cursor diagonally without releasing at a fast speed (1 quick flick).
Observe: the node remains at its initial position for one frame, then teleports to a position that does not match the cursor.

Expected Behavior

The node tracks the cursor continuously from the moment the drag threshold is crossed, with no visible offset between cursor and node anchor.

Actual Behavior

The node stays at its initial position during prepareDragSequence() and only starts following the cursor on the next pointermove event after the threshold pass. By that time the cursor has already travelled past the threshold by several px → the next onPointerMove applies a delta-from-mousedown that is much larger than expected → the node "snaps" to catch up.

Acceptance Criteria

No response

Browser

Firefox

[siarheihuzarevich]

Thanks for the clear repro on this one 🙌

Fixed in v19.0.0 (#314): the drag now anchors to the pointer-down position instead of the threshold-crossing point, and the first move applies immediately - so the node tracks the cursor from the very first frame, no catch-up jump on fast flicks.