What probably matters to youSection of the release
What
A plugin is an add-on package for Claude Code, described by a manifest file. The manifest gains a field for the versions of its hosts the plugin runs on. Under "claude-code", an author can give a range of Claude Code versions. If your Claude Code version is outside that range, the plugin is not installed, updated or loaded.
Separately, a marketplace's list of renamed plugins now copes with entries it cannot read instead of failing on them.
Why
Plugin authors can keep a plugin off Claude Code versions it does not support, so you are less likely to end up with a plugin that breaks on your version.