To support older browsers, Sizzle manipulates DOM by setting innerHTML property and then queries the results via querySelectorAll. This is problematic when Sizzle lib is used by a modern web app that enforces Trusted Types as all such assignments will fail.

It would be ideal to rewrite the code to avoid innerHTML and only use DOM manipulation methods such as createElement, appendChild or setAttribute. This might not be trivial though as such refactoring could change behavior in older browsers and break the functionality.

Alternatively, Sizzle could create custom Trusted Types policy and use method createHTML for all custom HTML strings.

See https://w3c.github.io/webappsec-trusted-types/dist/spec/ for more details about the spec.