Customized editor color is not exactly what I set

[dfxyz]

Type: Bug

I'm making a color theme for my VSCode. So I added following snippet into my settings.json:

"workbench.colorCustomizations": {
  "[*Light*]": {
    "editor.foreground": "#406080",
    "editor.background": "#F2FFE6",
  },
}

However, the result is:

• the actual foreground color is #4B5F7F
• the actual background color is #F5FFE6

VS Code version: Code 1.89.0 (b58957e, 2024-05-01T02:09:22.859Z)
OS version: Windows_NT x64 10.0.22631
Modes:

System Info

Item	Value
CPUs	AMD Ryzen 7 5700X 8-Core Processor (16 x 3400)
GPU Status	2d_canvas: enabled canvas_oop_rasterization: enabled_on 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 video_decode: enabled video_encode: enabled vulkan: disabled_off webgl: enabled webgl2: enabled webgpu: enabled
Load (avg)	undefined
Memory (System)	47.91GB (32.20GB free)
Process Argv	--crash-reporter-id 15cf8674-bd24-4554-8643-46ab83ef941b
Screen Reader	no
VM	0%

Extensions (27)

Extension	Author (truncated)	Version
copilot	Git	1.186.0
copilot-chat	Git	0.15.0
go	gol	0.41.4
rust-doc-viewer	JSc	4.2.0
intellij-idea-keybindings	k--	1.7.2
csharp	ms-	2.23.15
vscode-dotnet-runtime	ms-	2.0.3
black-formatter	ms-	2024.2.0
debugpy	ms-	2024.6.0
python	ms-	2024.6.0
vscode-pylance	ms-	2024.4.1
jupyter	ms-	2024.4.0
jupyter-keymap	ms-	1.1.2
jupyter-renderers	ms-	1.0.17
vscode-jupyter-cell-tags	ms-	0.1.9
vscode-jupyter-slideshow	ms-	0.1.6
cmake-tools	ms-	1.17.17
cpptools	ms-	1.19.9
cpptools-extension-pack	ms-	1.3.0
rust-analyzer	rus	0.3.1940
crates	ser	0.6.6
lua	sum	3.8.3
rust-pack	Swe	0.3.38
even-better-toml	tam	0.19.2
cmake	twx	0.0.17
vscode-lldb	vad	1.10.0
vim	vsc	1.27.2

(1 theme extensions excluded)

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