With 3.3.* the new composer resource checker is causing a container rebuild on every single page request, including profiler pages. This is caused by a difference in the cached php modules from the CLI while the request of the browser uses apache. I've added a picture of the differences between my webserver php and commandline php.

The check if the vendor/composer/installed.json is changed looks like a good change to me, but I don't think it should check the modules as well. If needed, I can provide a patch to remove the php module check, as we are unable to use 3.3 while this issue persists.