A browser only draws when the screen can show a new frame, so your display's refresh rate is the ceiling. On this PC the game itself runs at 800+ fps on Competitive, so the cap is the screen and the browser, not the game.
chrome://gpu should say WebGL is hardware accelerated."C:\Program Files\Google\Chrome\Application\chrome.exe" --user-data-dir="C:\ChromeUncapped" --disable-frame-rate-limit --disable-gpu-vsync http://localhost:5173