Up-arrow changing message box is bad

Type: <b>Bug</b>

I often use the Claude message box to prepare complex instructions. I often type up-arrow as part of editing the prompt I'm working on.

Lately I often have the experience of accidentally poping into the previous message. That message might be long and now I have to scroll back down and find the message I was working on, losing my train of thought, as if being interrupted in the middle of a sentence. It is annoying and frustrating, so much that I feel compelled to report it as a bug.

If you want the user to be able to get back to a previous message, give them a button. Don't overload basic editing keys.

Extension version: 2.1.145
VS Code version: Code - Insiders 1.122.0-insider (98454106993b96052992d1ece449759e4e1aceb2, 2026-05-22T10:00:03-07:00)
OS version: Darwin arm64 25.5.0
Modes:

<details>
<summary>System Info</summary>

|Item|Value|
|---|---|
|CPUs|Apple M4 (10 x 2400)|
|GPU Status|2d_canvas: enabled<br>GPU0: VENDOR= 0x106b [Google Inc. (Apple)], DEVICE=0x0000 [ANGLE (Apple, ANGLE Metal Renderer: Apple M4, Version 26.5 (Build 25F71))], DRIVER_VENDOR=Apple, DRIVER_VERSION=26.5 ACTIVE<br>Machine model name: Mac<br>Machine model version: 16.13<br>direct_rendering_display_compositor: disabled_off_ok<br>gpu_compositing: enabled<br>multiple_raster_threads: enabled_on<br>opengl: enabled_on<br>rasterization: enabled<br>raw_draw: disabled_off_ok<br>skia_graphite: enabled_on<br>trees_in_viz: disabled_off<br>video_decode: enabled<br>video_encode: enabled<br>webgl: enabled<br>webgl2: enabled<br>webgpu: enabled<br>webnn: disabled_off|
|Load (avg)|3, 3, 2|
|Memory (System)|24.00GB (0.75GB free)|
|Process Argv|--crash-reporter-id e15cc7ec-5f90-4b9b-a5d2-d043b996d22f|
|Screen Reader|no|
|VM|0%|
</details><details>
<summary>A/B Experiments</summary>

vsliv368cf:30146710
pythonvspyt551:31249597
nativeloc1:31118317
dwcopilot:31158714
dwoutputs:31242946
copilot_t_ci:31333650
g012b348:31231168
pythonrdcb7:31268811
pythonpcpt1cf:31399617
6518g693:31302842
6abeh943:31336334
envsactivate1:31349248
editstats-enabled:31346256
cloudbuttont:31366566
3efgi100_wstrepl:31403338
cmp-cht-control-3in1-xtab-294-3in1:31518747
cp_cls_t_966_ss:31454198
inlinechat_v2_hd992725:31445440
c0683394:31481635
8hhj4413:31478653
38bie571_auto:31426784
cp_cls_c_1081:31454833
conptydll_true:31485575
ia-use-proxy-models-svc:31446143
e9c30283:31453065
test_treatment2:31471001
46204921:31447328
idci7584:31454084
nes_chat_context_disabled:31451402
e3e4d672:31454087
ei9d7968:31462942
89g7j272:31506658
7e884298:31462391
7e187181:31482583
i2gc6536:31472020
52612955:31508042
h08i8180_copy:31475366
ec1eg703:31516426
ddid_c:31478205
hmra_i5g22:31518061
getcmakediagnosticson:31489824
f_rl1_7dj4g856:31518741
61f49681:31505879
7df3h592:31491241
cp_cls_t_1082:31516087
logging_enabled_new:31490725
nes-extended-cfe-himalia-004:31500349
jb_cp_cls_c_632:31517842
cg448276_tst_on:31503513
32d76977:31503652
ha629193:31508444
31fi7170_t:31517328
jh5f2457_c:31514653
95db8703:31517512
45j1j371_treat:31518485

</details>

<!-- generated by issue reporter -->