diff --git a/docs/implementation.md b/docs/implementation.md
index cf994bc..d3d9b23 100644
--- a/docs/implementation.md
+++ b/docs/implementation.md
@@ -1407,3 +1407,14 @@ Schwab still prints many forming ticks per frame. Those now coalesce to one
 `color-mix` shine. That cannot run on the compositor. Turning it off dropped
 tab CPU from ~20% to ~5%. The cue is now a 20px frame around the right-hand
 price label, opacity only.
+
+### 2026-08-31 — End trendline here was hidden unless the click was past last_t
+
+The context item only appeared when `cutoff > last_t`. A line whose second
+anchor already sits at or past the live edge never offered it; Duplicate and
+Delete still showed. The click does not move `last_t`. It sets `cutoff_t`,
+which clips drawing. Slope and both handles stay. Extend clears the cutoff.
+
+The menu now offers End here for any click after the earlier of the two
+anchors, including on the body between them and at `last_t` itself (that
+stops the projection without moving the end handle).