GitHub Copilot causing freeze/ performance issue when loading a webview from a editor context for a large files

[lcottercertinia]

Type: Performance Issue

Launch a webview from an editor context (editor/title/run contribution point) for a large causes a huge delay, the webview does not open for ~1 minute when the file is ~20mb. Opening the same web view from the explorer context (explorer/context contribution point) for the same file opens instantly.

prerequisite’s

• Github Copilot
• An extension which opens a webview (I used the apex log analyzer)

Steps

• Open a large file, larger than 6mb seems to trigger it, I used 20mb.
• Trigger the webview opening, I did this via editor/title/run.
• The webview takes ~40s to ~1 min to open.
• It used to be and should be near instant.

When the copilot extension is disabled the webview opens instantly.

Profile

I profiled the extensions following these steps

VS Code version: Code - Insiders 1.101.0-insider (496ebc4723371f29c9ffa0319dcccb2d7bee7ee0, 2025-05-21T05:04:29.987Z) OS version: Darwin x64 24.5.0 Modes:

System Info

Item	Value
CPUs	Intel(R) Core(TM) i7-1068NG7 CPU @ 2.30GHz (8 x 2300)
GPU Status	2d_canvas: unavailable_software canvas_oop_rasterization: disabled_off direct_rendering_display_compositor: disabled_off_ok gpu_compositing: disabled_software multiple_raster_threads: enabled_on opengl: disabled_off rasterization: disabled_software raw_draw: disabled_off_ok skia_graphite: disabled_off video_decode: disabled_software video_encode: disabled_software webgl: unavailable_software webgl2: unavailable_software webgpu: unavailable_software webnn: unavailable_software
Load (avg)	8, 9, 15
Memory (System)	16.00GB (1.43GB free)
Process Argv	--crash-reporter-id 58f6157f-0606-4c0f-9833-f97fff730019
Screen Reader	no
VM	0%