(DRAFT)
Support will be removed for legacy and core-based projects in Snapcraft 5.0 (expected July 22, 2021).
To continue using the core base, Snapcraft has opened a legacy 4.x track that maintains compatibility going forward. You may switch to this track using:
snap refresh snapcraft --channel=4.x/stable
We highly recommend migrating your snap to core20. For more information on migrating to core20, check out:
For more information on ESM and Snaps, check out: https://ubuntu.com/blog/how-does-ubuntu-16-04-entering-extended-security-maintenance-esm-affect-snap-publishers