news/plugins/email/vendor/doctrine/lexer/UPGRADE.md

Note about upgrading: Doctrine uses static and runtime mechanisms to raise awareness about deprecated code.

• Use of @deprecated docblock that is detected by IDEs (like PHPStorm) or Static Analysis tools (like Psalm, phpstan)
• Use of our low-overhead runtime deprecation API, details: https://github.com/doctrine/deprecations/

Upgrade to 2.0.0

AbstractLexer::glimpse() and AbstractLexer::peek() now return instances of Doctrine\Common\Lexer\Token, which is an array-like class Using it as an array is deprecated in favor of using properties of that class. Using count() on it is deprecated with no replacement.