revert modern ui update

Type: Feature Request

it does not look better - it creates roundness where not needed (eg tabs) and creates unhelpful space between elements. It's not a website where such cozyfied ui would fit. Instead, for me VSCode is a heavy loaded UI editor where plain line-split views make it easier to see what's where and do not crappen the picture with unusual odd no-real-benefit elements.

VS Code version: Code 1.129.0 (125df4672b8a6a34975303c6b0baa124e560a4f7, 2026-07-15T00:08:44Z)
OS version: Windows_NT x64 10.0.19045
Modes: Unsupported

System Info

|Item|Value|
|---|---|
|CPUs|AMD Ryzen 5 5500U with Radeon Graphics (12 x 2096)|
|GPU Status|2d_canvas: enabled
GPU0: VENDOR= 0x10de, DEVICE=0x1f9d [NVIDIA GeForce GTX 1650], DRIVER_VENDOR=NVIDIA, DRIVER_VERSION=32.0.16.1074 *ACTIVE*
GPU1: VENDOR= 0x1002, DEVICE=0x164c [AMD Radeon(TM) Graphics], DRIVER_VERSION=27.20.14032.15001
GPU2: VENDOR= 0x1414, DEVICE=0x008c [Microsoft Basic Render Driver], DRIVER_VERSION=10.0.19041.5794
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)|15.34GB (8.52GB free)|
|Process Argv|--file-uri file:///c%3A/dev/other/anomaly-packer-with-addon.code-workspace --enable-proposed-api TabNine.tabnine-vscode --crash-reporter-id 095bbcef-8f8b-4554-b2a9-b66875d21fd9|
|Screen Reader|no|
|VM|0%|
Extensions (29)

Name|Identifier|Author|Version
---|---|---|---
Carbon Product Icons|antfu.icons-carbon|antfu|0.2.9
Claude Code for VS Code|anthropic.claude-code|Anthropic|2.1.212
Copy without indent|aryeh.copy-without-indent|aryeh|0.0.4
All Autocomplete|atishay-jain.all-autocomplete|Atishay-Jain|0.0.26
Bearded Icons|beardedbear.beardedicons|BeardedBear|1.22.0
Tailwind CSS IntelliSense|bradlc.vscode-tailwindcss|bradlc|0.14.29
Catppuccin Icons for VSCode|catppuccin.catppuccin-vsc-icons|Catppuccin|1.26.0
Path Intellisense|christian-kohler.path-intellisense|christian-kohler|2.10.0
PostCSS Language Support|csstools.postcss|csstools|1.0.9
HTML CSS Support|ecmel.vscode-html-css|ecmel|2.0.14
Prettier - Code formatter|esbenp.prettier-vscode|esbenp|12.4.0
Auto Rename Tag|formulahendry.auto-rename-tag|formulahendry|0.1.10
GitHub Actions|github.vscode-github-actions|github|0.32.3
REST Client|humao.rest-client|humao|0.25.1
Background|katsute.code-background|Katsute|6.0.0
Discord Rich Presence|leonardssh.vscord|LeonardSSH|5.3.9
Svg Preview In Code|lzp.svg-preview-in-code|lzp|0.0.8
Rainbow CSV|mechatroner.rainbow-csv|mechatroner|3.24.1
SCSS IntelliSense|mrmlnc.vscode-scss|mrmlnc|0.10.0
Nash Icons|piscopancer.nash-icons|piscopancer|1.0.0
Prisma|prisma.prisma|Prisma|31.11.0
Language Support for Java(TM) by Red Hat|redhat.java|redhat|1.55.0
SCSS Formatter|sibiraj-s.vscode-scss-formatter|sibiraj-s|3.0.1
Even Better TOML|tamasfe.even-better-toml|tamasfe|0.21.2
vscode-pdf|tomoki1207.pdf|tomoki1207|1.2.2
TypeScript 7|typescriptteam.native-preview|TypeScriptTeam|0.20260708.2
Fonty|undefined_publisher.fonty|undefined_publisher|0.0.1
Error Lens|usernamehw.errorlens|usernamehw|3.28.0
Pretty TypeScript Errors|yoavbls.pretty-ts-errors|YoavBls|0.8.7

A/B Experiments

```
vsliv368cf:30146710
binariesv615:30325510
nativeloc1:31344060
dwcopilot:31170013
dwoutputs:31242946
copilot_t_ci:31333650
e5gg6876:31282496
pythonrdcb7:31342333
6518g693:31463988
aj953862:31281341
6abeh943:31336334
envsactivate1:31551504
cloudbuttont:31379625
3efgi100_wstrepl:31403338
ec5jj548:31422691
cp_cls_t_966_ss:31526232
4je02754:31466945
c3h7c220:31478652
38bie571_auto:31426784
cp_cls_c_1081:31454833
conptydll_true:31498968
e9c30283:31461165
test_treatment2:31471001
46204921:31447328
idci7584:31464702
e3e4d672:31494082
ei9d7968:31496641
chat:31457767
7e187181:31503455
githubstableflight:31469463
ghj88844:31499326
ec1eg703:31520046
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
852d2892:31506239
56dj4588:31512888
32d76977:31512328
ha629193:31508444
cdk-lw-on:31524445
f9bf7985:31543584
jh5f2457_c:31540921
8hfba999:31537718
jbcp_cls_pctr_t:31531130
61138546:31518536
cp_intellij_t_nes:31548657
gf14b233:31526830
8hjh2968:31552050
h561g132:31533256
sessions_5:31532894
ihg5j128:31534457
f412h606:31551416
7g2b5551:31542111
7642ad28:31552287
6i51c363:31551401

```