Why is --load-extension ignored by chrome-devtools-mcp?
When I run chrome-devtools-mcp with
--chromeArg="--load-extension=/path/to/extension"to test a browser extension, the extension never loads. The server launches Chrome with--disable-extensionsby default, which seems to override my flag. Is there a supported way to load an extension, or only a workaround?Originally asked on GitHub: https://github.com/ChromeDevTools/chrome-devtools-mcp/issues/698
3 answers
Status: explained — the issue was closed as a duplicate of #96 (opens external site), and a collaborator said proper extension debugging support is planned there. No fix landed in this issue.
The reporter passed
--chromeArg="--load-extension=/path/to/extension"to chrome-devtools-mcp while testing an extension with RTL positioning changes. The extension did not load, because chrome-devtools-mcp launches Chrome with--disable-extensionsby default and that flag overrides--load-extension.As a workaround, the reporter patched the package locally to enable extensions (commit linked in the issue) and said that works but is not ideal for distribution. Another commenter said a workaround linked from a comment on issue #265 worked for them, but the actual steps are not included in this thread — follow the linked comment if you want to try it.
A collaborator also said Chrome removed
--load-extensionaround M142, so the flag may not work on newer Chrome versions regardless of chrome-devtools-mcp.General advice: only load extensions you trust, since extensions can read and modify the content of pages the browser visits.
Did this work for you?What @diraneyya tried on GitHub (Didn't work)
Ran chrome-devtools-mcp with
--chromeArg="--load-extension=/path/to/extension"to test an extension with RTL positioning fixes for form fields. The extension did not load because the server launches Chrome with--disable-extensionsby default.Source: https://github.com/ChromeDevTools/chrome-devtools-mcp/issues/698 (opens external site)
Did this work for you?What @oleander tried on GitHub (Worked)
Reported that a workaround linked from a comment on issue #265 worked for them. The thread gives only the link, not the actual steps.
Did this work for you?
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