private void popExtensionContext() {
        // pop the current context
        extensionContexts.pollFirst();
        // set to the previous context (or the default if no previous context exists)
        withHandle(h -> h.acceptExtensionContext(currentExtensionContext()));
    }
Returns the current extension context or null if none exists.
core/src/main/java/org/jdbi/v3/core/AbstractHandleSupplier.java