C# keeps producing unsolicited notifications

[gregnexmos]

Type: Bug

Issue Description

Misleading notication cannot be turned off.

Steps to Reproduce

Pretty much any C# file that's too large or not parsable for any reason.

Expected Behavior

Ability to turn the unhelpful messages off. Stop covering a part of the screen I'm trying to look at.

Actual Behavior

Keeps producing "Request textDocument/documentHighlight failed." notifications over and over, i.e. when trying to resolve merge conflicts or pasting a piece of code into the windo.

Extension version: 2.136.19
VS Code version: Code 1.117.0 (10c8e557c8b9f9ed0a87f61f1c9a44bde731c409, 2026-04-21T16:12:14-07:00)
OS version: Windows_NT x64 10.0.26200
Modes:

System Info

Item	Value
CPUs	Intel(R) Core(TM) i7-10610U CPU @ 1.80GHz (8 x 2304)
GPU Status	2d_canvas: enabled GPU0: VENDOR= 0x8086, DEVICE=0x9b41 [Intel(R) UHD Graphics], DRIVER_VENDOR=Intel, DRIVER_VERSION=31.0.101.2137 ACTIVE GPU1: VENDOR= 0x1414, DEVICE=0x008c [Microsoft Basic Render Driver], DRIVER_VERSION=10.0.26100.8246 Machine model name: Machine model version: direct_rendering_display_compositor: disabled_off_ok gpu_compositing: enabled multiple_raster_threads: enabled_on opengl: enabled_on rasterization: enabled raw_draw: disabled_off_ok skia_graphite: disabled_off trees_in_viz: disabled_off video_decode: enabled video_encode: enabled webgl: enabled webgl2: enabled webgpu: enabled webnn: disabled_off
Load (avg)	undefined
Memory (System)	15.67GB (1.41GB free)
Process Argv	--folder-uri file:///d%3A/Project/Wastepack/Wastepack.Portal --crash-reporter-id 1cd56827-89d3-442c-9457-f0d0fe865627
Screen Reader	no
VM	0%

A/B Experiments

vsliv368:30146709
vswsl492cf:30256860
binariesv615:30325510
nativeloc1:31344060
dwcopilot:31170013
dwoutputs:31242946
copilot_t_ci:31333650
e5gg6876:31282496
pythonrdcb7:31342333
6518g693:31463988
aj953862:31281341
6abeh943:31336334
envsdeactivate2:31464701
cloudbuttont:31379625
3efgi100_wstrepl:31403338
ec5jj548:31422691
cp_cls_t_966_ss:31454198
inlinechat_v2_hd992725:31499106
4je02754:31466945
8hhj4413:31478653
ge8j1254_inline_auto_hint_haiku:31490510
38bie571_auto:31478678
cp_cls_c_1081:31454833
conptydll_true:31498968
ia-use-proxy-models-svc:31452481
e9c30283:31461165
test_treatment2:31471001
ts_provider_enabled:31458190
46204921:31447328
control_6dc23131:31497324
idci7584:31464702
e3e4d672:31494082
c-26112-aa:31454028
ei9d7968:31496641
534a6447:31496642
hg17d649:31458077
nes-extended-on:31455476
chat:31457767
8hig5102:31480529
quick_suggest_off_75197330:31497037
67jbj424:31500880
7e187181:31500884
cpptoolson-v2:31475363
i2gc6536:31499202
1g3cj959:31501677
ghj88844:31499326
23c7c724:31491644
client_tst_t:31495907
ddid_t:31478206
1b2f8594:31502054
getcmakediagnosticson:31489824
ja75b849:31495667
nes-perm-reb-1:31490410
pro_large_t:31499376
cp_cls_t_1082:31491633
719di409_sum_t:31499347
nes-cj-befline:31500936
logging_enabled_new:31498466
j0d79568:31499440
748c7209:31497895
nes-revagr-0:31501786