Skip to content

fix(mcp): Consider WAYLAND_DISPLAY for headed operation on Linux. #41265

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
smurfix wants to merge 2 commits into
base: main
Choose a base branch
from
+2 −2
Open

fix(mcp): Consider WAYLAND_DISPLAY for headed operation on Linux. #41265

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
c3dcaf9
Consider WAYLAND_DISPLAY for headed operation on Linux.
Jun 12, 2026
c43fb02
one more
Jun 12, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
2 changes: 1 addition & 1 deletion packages/playwright-core/src/tools/mcp/config.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -127,7 +127,7 @@ export async function resolveCLIConfigForMCP(cliOptions: CLIOptions, env?: NodeJ

const browser = await validateBrowserConfig(result.browser);
if (browser.launchOptions.headless === undefined)
browser.launchOptions.headless = os.platform() === 'linux' && !process.env.DISPLAY;
browser.launchOptions.headless = os.platform() === 'linux' && !process.env.DISPLAY && !process.env.WAYLAND_DISPLAY;

@dcrousso dcrousso Jun 12, 2026

Copy link
Copy Markdown
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

from what im reading it seems like $WAYLAND_DISPLAY is often a string, and some forums suggest setting it to something known to be nonexistent (e.g. WAYLAND_DISPLAY=no) so im not sure we can just falsy check it here

can you please give a bit more of an explanation as to your setup so we can better understand why this would solve the problem and is the best approach to do so?

@smurfix smurfix Jun 12, 2026

Copy link
Copy Markdown
Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I have no idea why people set WAYLAND_DISPLAY to "no" as opposed to simply unsetting it. Anyway, the reason somebody does this is most likely because they want to use X11 instead, i.e. DISPLAY is set anyway, so this is not a problem.

The reason why I need this is because X11 is widely considered to be fairly insecure all around; none of the tools I'm using need it any more; and because I want the installation to be as minimal as possible (don't want to assemble a Docker image with a heap of unused X11 libraries and all that …).

Alternate solution: add an explicit "--headed" option …

@yury-s yury-s Jun 12, 2026

Copy link
Copy Markdown
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Adding --headed sounds like a right approach if you deliberately want to run headed browser.


validateOutputDir(result.outputDir);

Expand Down
2 changes: 1 addition & 1 deletion packages/playwright/src/mcp/test/testContext.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -103,7 +103,7 @@ export class TestContext {
if (options?.headless !== undefined)
this.computedHeaded = !options.headless;
else
this.computedHeaded = !process.env.CI && !(os.platform() === 'linux' && !process.env.DISPLAY);
this.computedHeaded = !process.env.CI && !(os.platform() === 'linux' && !process.env.DISPLAY && !process.env.WAYLAND_DISPLAY);
}

private async _enqueue<T>(fn: () => Promise<T>): Promise<T> {
Expand Down
Loading