### Bug Description It may be useful to install two versions of snapcraft for testing changes to snapcraft itself. In this case, I am working on a new extension and the parallel installation of snapcraft isn't passed to LXD. Unrelated issue: #4683 ### To Reproduce After building snapcraft, install it in parallel to the existing stable snapcraft: ``` $ sudo snap install --classic --dangerous --name=snapcraft_env ./snapcraft_8.3.0.post10+git8442928db_amd64.snap snapcraft_env 8.3.0.post10+git8442928db installed ``` Then try to build a snap that uses this the newly developed extension: ``` $ SNAPCRAFT_ENABLE_EXPERIMENTAL_EXTENSIONS=1 snapcraft_env -v Starting snapcraft, version 8.3.0.post10+git8442928db Logging execution to '/home/farshid/.local/state/snapcraft/log/snapcraft-20240718-095346.533496.log' *EXPERIMENTAL* extension 'env-injector' enabled Launching managed ubuntu 24.04 instance... Starting instance Starting snapcraft, version 8.3.1 Logging execution to '/tmp/snapcraft.log' Starting snapcraft, version 8.3.1 Logging execution to '/tmp/snapcraft.log' Extension 'env-injector' does not exist Failed to execute snapcraft in instance. ``` ### Environment Ubuntu 23.10 ### snapcraft.yaml ```shell # Refer to https://github.com/canonical/snapcraft/pull/4925 for the extension name: envtester base: core24 version: 'demo' summary: Demonstration of env-exporter program description: | envtester is a demo snap to show the env-exporter program use cases grade: stable confinement: strict apps: myapp: daemon: simple environment: env_alias: myapp extensions: - env-injector command: run.sh parts: myapp: source: . plugin: dump # also need to create run.sh ``` ### Relevant log output ```shell - ``` ### Additional context I could not try with multipass as the provider, as I get some strange error, unrelated to the parallel installation: ``` SNAPCRAFT_BUILD_ENVIRONMENT=multipass SNAPCRAFT_ENABLE_EXPERIMENTAL_EXTENSIONS=1 snapcraft_env -v Starting snapcraft, version 8.3.0.post10+git8442928db Logging execution to '/home/farshid/.local/state/snapcraft/log/snapcraft-20240718-105347.585930.log' *EXPERIMENTAL* extension 'env-injector' enabled Launching managed ubuntu 24.04 instance... Incompatible base detected: Expected OS version '24.04', found '24.10'. Recommended resolution: Clean incompatible instance and retry the requested operation. ```