uPlot swallows the click that ends a drag, and decides a drag happened by
comparing the position it took at mousedown against the one it holds at
mouseup. It refines the first through `cursor.move` and re-reads the second
raw, never refining it (`mouseUp` -> `cacheMouse(initial: false)`), so with any
correction in place the two never agree: on a scaled panel every click on a
plot read as a drag and was stopped before it reached the page. A chart tile
could not be selected in the dashboard editor by clicking the chart, and a
Health chart could not be clicked to pin a moment.
Not the cursor correction being applied twice — that was a separate defect,
and idempotence could not have fixed this one, since the mouseup path never
applies the correction at all. Not `cursor.y` either: that only decides
whether the y cursor element is created, and both axes are read from the event
regardless.
Drag-to-zoom goes with it, and loses nothing: `setData` re-ranges the scales
from the data on every render, so a dragged range was erased by the next
reading. With no drag there is no click to protect from one.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016ZeGnqVsf5VHQqvz4HdUhN
stroblmeandClaude Opus 5
f58acfbd43