Completion text repeats while typing without accepting a suggestion

[AlissonKaelan]

Type: Bug

Issue Description

Steps to Reproduce

Expected Behavior

Actual Behavior

Extension version: 2.140.9
VS Code version: Code 1.134.0 (110a328ea54b42367b803ec53ee0bf52ef26b419, 2026-08-18T18:24:44Z)
OS version: Windows_NT x64 10.0.26200
Modes:

Logs

C# log

Details

2026-08-28 15:05:01.978 [info] Locating .NET runtime version 10.0.5
2026-08-28 15:05:02.844 [info] Dotnet path: c:\Users\Carollane\AppData\Roaming\Code\User\globalStorage\ms-dotnettools.vscode-dotnet-runtime\.dotnet\10.0.11~x64~aspnetcore\dotnet.exe
2026-08-28 15:05:02.844 [info] Activating C# + C# Dev Kit...
2026-08-28 15:05:03.040 [info] info: Program[0]
2026-08-28 15:05:03.041 [info]       Server started with process ID 12796
2026-08-28 15:05:03.806 [info] [Program] Language server initialized
2026-08-28 15:05:03.807 [info] [Program] Monitoring client process 9940 for exit
2026-08-28 15:05:04.525 [info] [initialized] [Microsoft.CodeAnalysis.LanguageServer.FileBasedPrograms.FileBasedProgramsEntryPointDiscovery] Finished discovery in '\\wsl.localhost\Ubuntu\home\alissonk\Projetos\CatalogoAPI' in 20 milliseconds
2026-08-28 15:05:08.965 [info] [serviceBroker/connect] [WorkspaceProjectFactoryService] Project \\wsl.localhost\Ubuntu\home\alissonk\Projetos\CatalogoAPI\CatalogoAPI.csproj loaded by C# Dev Kit
2026-08-28 15:06:35.112 [error] [textDocument/hover] [LSP] System.ArgumentOutOfRangeException: The requested line number 157 must be less than the number of lines 157. (Parameter 'Line')
   at Microsoft.CodeAnalysis.Text.TextLineCollection.GetPosition(LinePosition position) in /_/src/Compilers/Core/Portable/Text/TextLineCollection.cs:line 67
   at Microsoft.CodeAnalysis.LanguageServer.Extensions.GetPositionFromLinePositionAsync(TextDocument document, LinePosition linePosition, CancellationToken cancellationToken) in /_/src/LanguageServer/Protocol/Extensions/Extensions.cs:line 219
   at Microsoft.CodeAnalysis.LanguageServer.Handler.HoverHandler.GetHoverAsync(Document document, LinePosition linePosition, IGlobalOptionService globalOptions, Boolean supportsVSExtensions, Boolean supportsMarkdown, CancellationToken cancellationToken) in /_/src/LanguageServer/Protocol/Handler/Hover/HoverHandler.cs:line 76
   at Microsoft.CommonLanguageServerProtocol.Framework.QueueItem`1.StartRequestAsync[TRequest,TResponse](TRequest request, TRequestContext context, IMethodHandler handler, CancellationToken cancellationToken)
2026-08-28 15:06:35.116 [error] Request textDocument/hover failed.
  Message: The requested line number 157 must be less than the number of lines 157. (Parameter 'Line')
  Code: -32000 
[object Object]

C# LSP Trace Logs log

Details

Environment Information

VSCode version: 1.134.0
C# Extension: 2.140.9
Using OmniSharp: false

Dotnet Information

Host:
Version: 10.0.11
Architecture: x64
Commit: e2f47b0110
RID: win-x64

.NET SDKs installed:
No SDKs were found.

.NET runtimes installed:
Microsoft.AspNetCore.App 10.0.11 [c:\Users\Carollane\AppData\Roaming\Code\User\globalStorage\ms-dotnettools.vscode-dotnet-runtime.dotnet\10.0.11x64aspnetcore\shared\Microsoft.AspNetCore.App]
Microsoft.NETCore.App 10.0.11 [c:\Users\Carollane\AppData\Roaming\Code\User\globalStorage\ms-dotnettools.vscode-dotnet-runtime.dotnet\10.0.11x64aspnetcore\shared\Microsoft.NETCore.App]

Other architectures found:
None

Environment variables:
DOTNET_CLI_UI_LANGUAGE [en-US]
DOTNET_MULTILEVEL_LOOKUP [0]
DOTNET_NOLOGO [true]

global.json file:
Not found

Learn more:
https://aka.ms/dotnet/info

Download .NET:
https://aka.ms/dotnet/download

Visual Studio Code Extensions

Extension	Author	Version	Folder Name
csdevkit	ms-dotnettools	3.20.199	ms-dotnettools.csdevkit-3.20.199-win32-x64
csharp	ms-dotnettools	2.140.9	ms-dotnettools.csharp-2.140.9-win32-x64
csharp-dev-tools	JakubKozera	1.10.15	jakubkozera.csharp-dev-tools-1.10.15
github-copilot-code-reviewer	jakubkozera	0.22.2	jakubkozera.github-copilot-code-reviewer-0.22.2
ms-sql-manager	jakubkozera	0.20.4	jakubkozera.ms-sql-manager-0.20.4
vscode-containers	ms-azuretools	2.5.0	ms-azuretools.vscode-containers-2.5.0
vscode-dotnet-runtime	ms-dotnettools	3.1.0	ms-dotnettools.vscode-dotnet-runtime-3.1.0

C# Settings

Setting	Value
preferCSharpExtension	false
compilerDiagnosticScope	openFiles
analyzerDiagnosticScope	openFiles
enableXamlTools	true
useServerGC	true

System Info

Item	Value
CPUs	12th Gen Intel(R) Core(TM) i5-12450H (12 x 2496)
GPU Status	2d_canvas: enabled GPU0: VENDOR= 0x10de, DEVICE=0x25ed [NVIDIA GeForce RTX 2050], DRIVER_VENDOR=NVIDIA, DRIVER_VERSION=32.0.15.6094 ACTIVE GPU1: VENDOR= 0x1414, DEVICE=0x008c [Microsoft Basic Render Driver], DRIVER_VERSION=10.0.26100.8972 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 webgpu: enabled webnn: disabled_off
Load (avg)	undefined
Memory (System)	15.80GB (4.44GB free)
Process Argv	--crash-reporter-id 76a80715-3cd2-441b-9ba4-6949dd3a6b95
Screen Reader	no
VM	0%

A/B Experiments

vsliv368:30146709
pythonvspyt551cf:31249601
binariesv615:30325510
nativeloc1:31344060
dwcopilot:31170013
dwoutputs:31242946
copilot_t_ci:31333650
e5gg6876:31282496
pythonrdcb7:31342333
6518g693:31463988
aj953862:31281341
4f60g487:31327383
envsactivate1:31551504
478i5457:31544283
cloudbuttont:31379625
3efgi100_wstrepl:31403338
ddidt:31399633
ec5jj548:31422691
cp_cls_t_966_ss:31526232
4je02754:31466945
8hhj4413:31478653
cp_cls_c_1081:31454833
conptydll_true:31498968
e9c30283:31461165
46204921:31447328
capico_axe_098a3278:31555651
ei9d7968:31496641
chat:31457767
8hig5102:31480529
89g7j272:31518289
i2gc6536:31499202
52612955:31516516
23c7c724:31520045
ddid_c:31478207
hmra_i5g22:31518061
7df3h592:31512476
cp_cls_t_1082:31535311
logging_enabled_new:31498466
db5d2638:31499441
jb_cp_cls_t_632:31543129
56dj4588:31512888
32d76977:31512328
ha629193:31508444
jh5f2457_c:31540921
jbcp_cls_pctr_t:31531130
61138546:31518536
cp_intellij_t_nes:31548657
jf4hg949:31526829
ahp-both-windows:31556933
sessions_3:31532893
ihg5j128:31534457
f412h606:31551416
7g2b5551:31542111
nes-ex-cf-euporie-03:31542868
enable_editor_pane_layout:31569726
allow-none:31555437
36h42362:31564511
c7c27ce7:31554789
1h923230:31564177
1532g621_copy:31554320
treatment-23-1:31555779
unuse_dynamic_mcp:31555281
0d8dfbc3:31570291
0c1h4866:31566224
session-archive:31558132
5b8j3302:31564601
mangle-name-treatment:31572634
permission_prompt_treatment:1332566
ccr_pr_nudge_control:1319470
vsc_wsm_t:1340632
eh853263:1355661

[dibarbet]

Thanks for the report. If you can reproduce this, please record the C# LSP trace logs: https://github.com/dotnet/vscode-csharp/blob/main/SUPPORT.md#capturing-activity-trace-logging. Please also confirm whether it reproduces with the latest C# extension pre-release.