I stumbed upon the same issue that #22149 but with this component, when the project root dir is under open_basedir restriction, this the LinkStub::getComposerRoot() will fail finding the composer.json file, under certain circumstances, depending on the PHP configuration and version, this may end up in a fatal error making it impossible to work with a 'dev' environment in such case.

Steps to reproduce:

• enable open_basedir, exclude the project root dir from it, allow only app, public, src, vendor directories in open_basedir configuration;
• manually clear all caches and attempt to access site with the debug bundle activated.

I have no clue on fixing this one, but it would be nice if it could use the project.root_dir variable instead, maybe by injecting it. Problem is, all usages are done in the component itself, it would need to inject the path in pretty much every class that uses it, which would make a patch very invasive, and would potentially make it a BC break.