diff --git a/memory.md b/memory.md
index dedafa1..cb38d7a 100644
--- a/memory.md
+++ b/memory.md
@@ -108,6 +108,16 @@ Four-agent research pass (terminal-landscape, AI-orchestration, xterm/Tauri ecos
 
 ## Session log
 
+### 2026-06-11 — NEW user-reported cursor bug (diagnosis pending user A/B test)
+
+**Symptom:** typing in a pane, the cursor "gets stuck" / shows a gap between typed text and the cursor block; after a few seconds of not typing the gap "vanishes" (display snaps correct). User Q&A: only noticed **inside claude** (not confirmed at plain bash); **a few seconds** to self-correct; unknown whether visual-only or a real eaten character. Distinct from the 2026-05-28 stuck/ghost cursor (that was the DOM renderer leaving a stale block; fixed via canvas addon).
+
+**Leading hypothesis: Claude Code TUI input-render buffering, not tiletopia.** Claude's Ink TUI does render+stdin on one event loop; under load it buffers keystroke echo and flushes in a batch — cursor lags/gaps then catches up. Documented upstream: claude-code #58498 (input invisible/cursor frozen, dumps at once), #63504 (Windows host CPU pressure starves input loop), #29366, #2847. Running many parallel claudes (tiletopia's whole purpose) = exactly the CPU-contention trigger.
+
+**Decisive test (user to run):** same distro, run `claude` in Windows Terminal, type fast mid-session — if it reproduces there, it's claude upstream, not tiletopia. Also check whether it correlates with number of busy panes.
+
+**If tiletopia-implicated:** note `@xterm/addon-canvas` is now **deprecated upstream** (no fixes, removed in xterm v6; webgl is the recommended path — would need context-pool management given the ~16 WebGL context cap with many panes; xterm 5.5's DOM renderer is faster than when we abandoned it but would regress the 05-28 ghost-cursor fix). Renderer swap is the lever ONLY if the A/B test pins it on tiletopia.
+
 ### 2026-06-01 — Customizable terminal colors (global theme + per-pane override), v0.4.1
 
 **Feature:** user-editable terminal colors. Scope = **global default + per-pane override** (both, per the user's choice). Editable colors = **background / foreground / cursor / selection** only (NOT the full 16-color ANSI ramp — explicitly out of scope). UI = **modal + presets**.