Copilot painfully slow - barely usable

[cb1d]

Type: Bug

I am using Copilot in VSCode for 2-3 weeks now in Agent Mode. And over the time, it has become painfully slow, especially in the last few days. I followed some advice from forum entries I found and disabled all extensions to find a culprit. Acutally I only have CMake (Microsoft) plus Github Copilot and Copliot Chat enabled, all other Extensions are disabled (Microsoft C/C++, C/C++ Extenstion pack and Makefile Tools). And it is still barely usable. The whole UI is slow and reacts with delay (even the Issue reporter window). When I open the Developer Tools I see a lot of entries like >>potential listener LEAK detected, having 195 listeners already. MOST frequent listener (11):: Error<<

VS Code version: Code 1.105.1 (7d842fb, 2025-10-14T22:33:36.618Z)
OS version: Windows_NT x64 10.0.26200
Modes:

System Info

Item	Value
CPUs	Intel(R) Core(TM) i7-10700 CPU @ 2.90GHz (16 x 2904)
GPU Status	2d_canvas: enabled 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 vulkan: disabled_off webgl: enabled webgl2: enabled webgpu: enabled webnn: disabled_off
Load (avg)	undefined
Memory (System)	31.70GB (22.42GB free)
Process Argv	--crash-reporter-id 20f07d02-3646-4fe7-9798-32548ee9daea
Screen Reader	no
VM	0%

Extensions (3)

Extension	Author (truncated)	Version
copilot	Git	1.388.0
copilot-chat	Git	0.32.4
cmake-tools	ms-	1.21.36

[cb1d]

Update: i just uninstalled VSCode, followed the instructions for a clean uninstall from https://code.visualstudio.com/docs/setup/uninstall (deleted %APPDATA%\Code and %USERPROFILE%.vscode). Then reinstalled it with only Copilot, Copilot Chat and CMake-Tools Extensions. Facit: The Developer Tools Console still shows many lines like this one: >>ERR [13d] potential listener LEAK detected, having 208 listeners already. MOST frequent listener (36):: Error<<

I am using mainly the Copilot-Chat in Agent mode. And it is still very slow.

The last Error entry is this one:

ERR [13d] potential listener LEAK detected, having 208 listeners already. MOST frequent listener (36):: Error
at qAi.create (vscode-file://vscode-app/c:/Users/cb/AppData/Local/Programs/Microsoft%20VS%20Code/resources/app/out/vs/workbench/workbench.desktop.main.js:27:11992)
at fJe.u [as onModelAdded] (vscode-file://vscode-app/c:/Users/cb/AppData/Local/Programs/Microsoft%20VS%20Code/resources/app/out/vs/workbench/workbench.desktop.main.js:29:1377)
at new Qi (vscode-file://vscode-app/c:/Users/cb/AppData/Local/Programs/Microsoft%20VS%20Code/resources/app/out/vs/workbench/workbench.desktop.main.js:507:36931)
at new v1e (vscode-file://vscode-app/c:/Users/cb/AppData/Local/Programs/Microsoft%20VS%20Code/resources/app/out/vs/workbench/workbench.desktop.main.js:1633:20005)
at cDt.o (vscode-file://vscode-app/c:/Users/cb/AppData/Local/Programs/Microsoft%20VS%20Code/resources/app/out/vs/workbench/workbench.desktop.main.js:1398:1716)
at cDt.createInstance (vscode-file://vscode-app/c:/Users/cb/AppData/Local/Programs/Microsoft%20VS%20Code/resources/app/out/vs/workbench/workbench.desktop.main.js:1398:1213)
at y1e.r (vscode-file://vscode-app/c:/Users/cb/AppData/Local/Programs/Microsoft%20VS%20Code/resources/app/out/vs/workbench/workbench.desktop.main.js:1633:27772)
at vscode-file://vscode-app/c:/Users/cb/AppData/Local/Programs/Microsoft%20VS%20Code/resources/app/out/vs/workbench/workbench.desktop.main.js:1633:26284
at NodeList.forEach ()
at y1e.walkTreeAndAnnotateReferenceLinks (vscode-file://vscode-app/c:/Users/cb/AppData/Local/Programs/Microsoft%20VS%20Code/resources/app/out/vs/workbench/workbench.desktop.main.js:1633:25613)

[DIESLTEK710]

i am as well having github copilot being incredibly slow! especially the past 2-3 weeks. i was just about to contact about this issue until this appeared.. for simple prompts quickest response ill get is min 20min.. its slower than dialup! i have checked updates, check settings, i still have credits.. etc.. ive only been able to do maybe 10 prompts a day lately if im lucky.. but even 20min is being generous..

[deepak1556]

Can you share performance profile following the steps here https://github.com/microsoft/vscode/wiki/Performance-Issues#profiling-the-renderer-process

[akaymakci]

I am having the similar issues, I think AI sucked.