An error occurs when switching to the edge browser：SyntaxError: browserType.launch: Invalid URL: undefined

[GdmnKomo]

Below is my configuration fil:

Then here is my error message. This problem has been bothering me for a long time. When I use the initial google, it will report an error because the same browser exists. Then the project I need to test is always preparing to switch from ie to edge. An error was reported after the switch. I'm really speechless.

What I can confirm is that the edge browser exists at that location on the c drive

[pavelfeldman]

Can't repro this

[s-e-e-s]

i use Gemini CLI have the same problem. then i used the .py to call playwright and it works fine.
it seems that the problem is from Gemini CLI.

`
from playwright.sync_api import sync_playwright
import time

def run_test():
try:
with sync_playwright() as p:
browser = p.chromium.launch(channel="msedge", headless=False)

        print(">>> 浏览器启动成功！")

        page = browser.new_page()

        url_to_visit = "https://www.bing.com"
        print(f">>> 准备导航到: {url_to_visit}")

        # 直接调用 goto 函数，传入一个明确的 URL 字符串
        page.goto(url_to_visit)

        print(f">>> 成功打开页面: {page.title()}")

        # 保持浏览器打开10秒，以便你观察
        time.sleep(10)

        browser.close()
        print(">>> 浏览器已关闭。测试成功！")

except Exception as e:
    print(f"!!! 测试过程中发生错误: {e}")

if name == "main":
run_test()
`

[GdmnKomo]

@s-e-e-s So, do you have any good ideas? I'm stuck here now and don't know how to use it because I want to use it for automated linkage processes

[GdmnKomo]

Can't repro this 不能复制这个

@pavelfeldman What's outrageous is that even when I restored it to the initial configuration of chrome, it still didn't work. It will show that there are the same browser instances running

[GdmnKomo]

I found a great solution that perfectly avoids the 'browser is already' and 'browser type undefined' errors. Not sure how long this configuration will last without issues, but it seems to be working fine for now. I can open Edge normally.

[kalulas]

I am using playwright-mcp with claude code (on Windows), and this configuration solves my problem (also using msedge)

        "playwright": {
          "command": "cmd",
          "args": [
            "/c",
            "npx",
            "@playwright/mcp@latest",
            "--browser",
            "msedge",
            "--storage-state=[your-storage-json-file]",
            "--user-data-dir=[your-user-data-directory]"
          ]
        }

This could be useful if you want to keep persistent storage instead of --isolated

[pavelfeldman]

Closing as per above.

[yury-s]

@GdmnKomo @kalulas which Node.js and npm versions does the error happen on? My hunch is that the error has something to do with npm/cli#6548 given that it goes away if running with cmd /c.